USOO6894082B2 (12) United States Patent (10) Patent No.: US 6,894,082 B2 Brant et al. (45) Date of Patent: May 17, 2005

(54) FOAMABLE COMPOSITIONS 4,180,640 A 12/1979 Melody et al...... 526/323.1 4,287,330 A 9/1981 Rich ...... 526/270 (75) Inventors: Karen R. Brant, West Springfield, MA 4,321,349 A 3/1982 Rich ...... 526/270 (US); Philip T. Klemarczyk, Canton 4,686,244 A 8/1987 Dietlein et al...... 523/179 CT (US) s s 4,808.634 A 2/1989 Uriarte et al...... 521/87 4.954,415 A 9/1990 Davis et al...... 430/138 5,061,736 A 10/1991 Takahashi et al...... 521/91 (73) Assignee: Henkel Corporation, Rocky Hill, CT 5,246,973 A 9/1993 Nakamura et al...... 521/54 (US) 5,356,940 A 10/1994 Giesen ...... 521/77 c: - 5,358,975 A 10/1994 Anderson .. ... 521/77 (*) Notice: Subject to any disclaimer, the term of this 5,373,021. A 12/1994 Marangos .. ... 514/483 patent is extended or adjusted under 35 5,575,526. A 11/1996 Wycech ...... 296/205 U.S.C. 154(b) by 147 days. 5,900.438 A 5/1999 Miyoshi et al...... 521/77 6,003,274. A 12/1999 Wycech ...... 52/232 6,092.864 A 7/2000 Wycech et al...... 296/204 (21) Appl. No.: 10/243,853 6,110,982 A 8/2000 Russick et al...... 521/54 (22) Filed: Sep. 16, 2002 6,207,730 B1 3/2001 Hogan, III ...... 523/219 6.218.442 B1 4/2001 Hilborn et al...... 521/85 (65) Prior Publication Data 6,277.898 B1 8/2001 Pachl et al...... 522/100 6,562,878 B2 * 5/2003 Blank et al...... 521/50.5 US 2004/0063800 A1 Apr. 1, 2004 6,638,635 B2 * 10/2003 Hattori et al...... 428/500 (51) Int. Cl...... C08J 9/06, C08908; 3 cited by examiner CO8J 9/10 (52) U.S. Cl...... 521/50.5. 521/89, 521/120; Primary Examiner Morton Foelak 521/142: 521/147; 522/75; 522/96; 522/114; (74) Attorney, Agent, Or Firm-Steven C. Bauman 522/117 (57) ABSTRACT (58) Field of Search ...... 521/50.5, 89, 120, 521/142, 147; 522/90, 75, 96, 114, 117 This invention relates to latent foamable compositions for use in or as adhesives, Sealants and/or coatings. The com (56) References Cited positions include a curable component or a thermoplastic component, together with a latent foaming agent. In curable U.S. PATENT DOCUMENTS versions of the inventive compositions, a cure initiator or 3,218,305. A 11/1965 Krieble ...... 260/89.5 catalyst may also be included. 3.425,964 A 2/1969 Henry ...... 260/2.5 3.592,782 A 7/1971 Weber ...... 260/2.5 25 Claims, 1 Drawing Sheet

11

-Acetyl Thiohydroxamate - - - Palmitoyl Thiohydroximate 0 - - - Oleoyl Thiohydroximate U.S. Patent May 17, 2005 US 6,894,082 B2

US 6,894,082 B2 1 FOAMABLE COMPOSITIONS N A BACKGROUND OF THE INVENTION O N S hw Her 1. Field of the Invention N This invention relates to latent foamable compositions for R use in or as adhesives, Sealants and/or coatings. The com positions include a curable component or a thermoplastic o-Acylthiohydroxamate, 1 component, together with a latent foaming agent. The latent N : foaming agent is capable of ambient temperature perfor mance when exposed to UV radiation, or elevated tempera N 15 N S ture performance. In curable versions of the inventive 2. 2 eq. 1 compositions, a cure initiator or catalyst may also be N S included. 2. Brief Description of Related Technology The commercial marketplace for adhesives, coatings and |one sealants, which are cured by exposure to UV or visible light Polymer radiation, is a rapidly growing Segment of the adhesives industry. The advantages of such UV or visible light curing include providing products with a larger percentage of 25 reactive materials, on-demand curability, fast curability, minimized opportunity to compromise the integrity of the Alkylpyridylsulfide, 2 parts to be bonded or Sealed, and lower energy consumption, as contrasted to conventional heat cure processing. To date, however, it has not been recognized or reported Perhaps the most widely used UV or visible light curing that Such materials may form the basis for a foaming System, formulations, which are initiated by free radicals, include particularly for use in a plastic matrix. generally mono- and di-functional (meth) acrylate monomers, a photoinitiator, and optionally, an acrylate 35 Rather, creating foamed polymers generally involves the functional pre-polymer. The phototinitiator generates free use of for example a blowing agent, which yields a gas on radicals on exposure to UV or visible light that initiate cure. thermal exposure, the production of carbon dioxide by the However, (meth)acrylate based formulations are known to reaction of a diisocyanate with water, or the generation of a possess certain limitations generally, including oxygen inhi foam by the addition of a gas or low boiling liquid to a bition of (meth)acrylate polymerization at the air/coating 40 molten polymer. To that end, many foamable compositions are known. See e.g. U.S. Pat. Nos. 4,686,244 (Dietlin) and interface, limited cure through depth, and difficulty in curing 5,246,973 (Nakamura). See also U.S. Pat. Nos. 4,808,634 highly pigmented Systems. (curable foaming silicone composition containing a vinyl Various methods have been studied to overcome or mini polysiloxane, a hydride polysiloxane, a hydroxyl Source 45 Selected from organic alcohol or organic alcohol in combi mize oxygen inhibition at the coating/air interface, Such as nation with water or hydroxylated organosiloxane, from 1 to the use of high intensity light, dual-cure mechanisms, or about 250 ppm of platinum catalyst and a ketoximine placing a physical barrier over the coating. compound effective to lower the foam density. Foam is The use of O-acylthiohydroxamates has been reported to created through the reaction of the hydride polysiloxane 50 with the hydroxy Source to liberate hydrogen gas.); 5,358, reduce the tack free time of UV curable coatings, to which 975 (organosiloxane elastomeric foams, incorpoarting a they have been added. Indeed, in U.S. Pat. No. 4,954,415 triorganosiloxy end-blocked polydiorgano Siloxane, an orga (Davis), a photohardenable composition including a free nohydrogen Siloxane, a platinum catalyst, an O, B, ()-diol radical addition polymerizable material and a photoinitiator and a resinous copolymer containing Siloxy vinyl groups. composition is claimed. The photoinitiator composition 55 Foaming is produced as a result of the reaction of the includes a compound, which absorbs actinic radiation and polyhydrogen siloxane and the alcohol which liberate hydro directly or indirectly generates free radicals, and an gen gas.); 6,110,982 and 5,373,027 (use of blowing agents o-acylthiohydroxamate or an N-alkoxypyridinethione. The to effectuate foams); 6,207,730 B1 (epoxy composition to compositions described in the 415 patent were developed which is added thermoplastic shell microSpheres, which may for and are reported as useful in photoimaging applications. 60 encapsulate a gas.); 6,277,898 B1 (epoxy resins useful as photocurable paints which use chemical or mechanical o-Acylthiohydroxamates generally decompose on expo expansion agents to create foams.); and 5,356,940 (fine sure to UV radiation to provide radicals, which can either pored Silicone foam which is formed by mixing a vinyl recombine or initiate acrylate polymerization at the Surface Silicone, an organo-platinum catalyst, fumed Silica, and to overcome oxygen inhibition, as Seen below in eq. 1. The 65 water as a first part, with a Second part which includes a major by-product of the reaction is an alkylpyridyl Sulfide, Silicone polymer having at least two double bonds per 2. molecule, fumed Silica and polydimethylhydrogensiloxane. US 6,894,082 B2 3 4 The two components are mixed and the reaction is Subse portion, or both, with reactive groups Such as (meth) quently pressurized, using air or nitrogen, So that the pres acrylates, alkoxides (attached to a Silicone atom, or silylated Surized gas is present in the mixture in a dissolved form. alkoxides), aryloxides (attached to a silicone atom, or Sily Subsequently, the reaction mixture is heated and the dis lated aryloxides), Vinyls (attached to a Silicone, or Sillylated Solved gas is released, thereby forming a fine pored Silicone vinyls), Vinyl ethers, hydrides (attached to a silicone atom, foam.); 5,900,430 (silicone foaming compositions which or Silicon hydrides), hydroxyls, isocyanates and epoxies, as contain an organopolysiloxane containing a specified well as combinations thereof. amount of an alkenyl group and/or a hydroxyl group, an The oligomers and polymerS may be Selected from a organohydrogenpolysiloxane, a compound having an active wealth of possibilities, examples of which are given below. hydrogen, Such as an alcohol, a platinum catalyst and an An initiator or catalyst component may also be included, acetylenic alcohol compound. Foaming occurs during the and when included may be chosen from radiation triggered cure process by the reaction of the compound having an initiators or catalysts, or thermally triggered initiators or active hydrogen group, i.e., an alcohol, with the organohy catalysts. In addition, anaerobic cure inducing compositions drogenpolysiloxane compound to release hydrogen gas.); may also be included. 5,061,736 (foamable silicone compositions useful as fire 15 The inventive latent foaming agent is within the following resistant joint-Sealing members. The compositions disclosed Structure I contain a diorganopolysiloxane, a finely divided reinforcing Silica filler, a powder of a ferrite Such as a divalent metallic element Such as manganese, copper, nickel, from 10 to 70 parts by weight of a finely divided inorganic material, Such as mica or glass powders, finely divided platinum metal, a R2 curing agent for Silicone rubberS Such as a peroxide or X condensation catalyst, and the blowing agent is a composi S tion which produces a foaming gas when exposed to elevated temperature, Such as nitrogen, carbon dioxide, 25 azobisiobutyronitrile.); 6,003,274 (reinforcement web for a where R is H, C alkyl, with or without interruption or hollow Structural member having layer of expandable Substitution by oxygen, Sulfur, and nitrogen, R is C-2 foam-a resin-based material containing a blowing agent alkyl, with or without interruption or Substitution by Oxygen, dispersed on its principal Surfaces.); 5,575,526 and 6,092, Sulfur, nitrogen, aralkyl, and C- alkenyl, X is carbon or 864 (laminates which have support members or beams Sulfur, Z is a Single bond or double bond, and a is 0 or 1, m bonded together with a structural foam layer, produced by a is 0-4, and n is 1-4. synthetic structural resin combined with a cell-forming Desirably, when X is carbon, Z is a double bond and a is agent (blowing agent) and hollow microspheres); 6,218,442 1 and n is 1, and when X is Sulfur, Z is a Single bond, a is B1 (corrosion-resistant foam formulation which includes 0 and n is 1. one or more thermosettable Synthetic resins, one or more 35 More specific examples of the photo-induced foaming curatives, one or more blowing agents and one or more agent are within the following Structures II and III, respec organic titanates or Zirconates.) tively Notwithstanding the state-of-the-art, it would be desirable to provide a latent foaming agent for use with a matrix (R) whether or not curable-, which matrix is destined for use 40 O in applications where foaming or dimensional expansion /- may be desirable. C-O-N / SUMMARY OF THE INVENTION The present invention is directed to a latent foamable 45 composition, which includes a matrix component, which may be a curable and/or thermoplastic component, and a where R is is H, C, alkyl, with or without interruption or latent foaming agent. Where a curable component is present, Substitution by oxygen, Sulfur, and nitrogen, R is C-2 it is often desirable to provide an initiator or catalyst alkyl, with or without interruption or Substitution by Oxygen, component, as well. 50 Sulfur, nitrogen, aralkyl, and C- alkenyl, m is 0-4, and in is 1-4. Upon exposure to conditions Sufficient to foam the inven tive compositions, an increase in dimension is observed to occur in at least one direction. For instance, at a concentra tion of 2 phr of the latent foaming agent, the inventive 55 compositions may increase in height by 8%, at a concen / tration of 3 phr of the latent foaming agent, the inventive compositions may increase in height by 84%, and at a concentration of 4 phr of the latent foaming agent, the inventive compositions may increase in height by 113%. 60 With heat-induced foamable compositions, at a concen where R is is H, C, alkyl, with or without interruption or tration of 8 phr of the latent foaming agent, the inventive Substitution by oxygen, Sulfur, and nitrogen, R is C-2 compositions may increase in height by 100%. alkyl, with or without interruption or Substitution by Oxygen, The matrix component may be selected generally from Sulfur, nitrogen, aralkyl, and C alkenyl, m' is 0–2, and n' curable monomers, oligomers and polymers, and thermo 65 is 1-4. plastic oligomers and polymers. The curable component In another aspect, the present invention is directed to a may be functionalized either in the terminal portion, pendant method of making a foamable composition. The method US 6,894,082 B2 S includes the Steps of providing a matrix component; pro Viding a latent foaming agent; and mixing together the matrix component and the latent foaming agent. In a further aspect, the present invention is directed to a method of foaming a latent foamable composition. This X method includes the Steps of dispensing the foamable com O S position onto at least a portion of a first Substrate, exposing the dispensed composition to conditions appropriate to foam the composition and mating to the foamed composition a where R is is H, C, alkyl, with or without interruption or Second Substrate to form an article mated with the foamed Substitution by oxygen, Sulfur, nitrogen, and aryl, R is C-2 composition. And a foamed composition is formed between alkyl, with or without interruption or Substitution by Oxygen, Sulfur, nitrogen, aralkyl and C-2 alkenyl, m' is 0–2, and n' the parts of the article. is 1-4. 15 Examples of compounds comprising Structure II include BRIEF DESCRIPTION OF THE FIGURE and aliphatic and a licy clic e Sters of N-hydroxythiohydroxamate. Specific examples include 3,3- diphenylpropionyl thiohydroxamate, 1-methylcyclohexyl FIG. 1 depicts TGA analysis for acetyl thiohydroxamate, carbonyl thiohydroxamate, acetylthiohydroxamate, propio 3, palmitoyl thiohydro Xamate, 6, and ole oyl nyl thiohydroxamate, octanoyl thiohydroxamate, palmitoyl thiohydroxamate, 7, indicating decomposition beginning at thiohydroxamate, oleoyl thiohydroxamate, and cyclopen temperatures about 100 C. tanoylthiohydroxamate, though a particularly desirable one is palmitoyl thiohydroxamate, shown below.

DETAILED DESCRIPTION OF THE 25 O o INVENTION CH-C-O-N The present invention is directed to a matrix component, which may be curable and/or thermoplastic, and a latent foaming agent. The latent foaming agent includes com pounds comprising the following structure I Additional Specific examples of compounds comprising structure III include O-esters of 4-methyl-N-hydroxy thia (R')n Zolethione. Specific examples include 3-palmitoyl-4-phenyl O == 35 thiazolethione, and 3,3-diphenylpropionyl thiazolethione, though a particularly desirable one is palmitoyl R2 / y thiazolethione, shown below. X X CH S 40 s O-N S where R' is H, C, alkyl, with or without interruption or C15H31 Substitution by oxygen, Sulfur, and nitrogen, R is C-2 O S alkyl, with or without interruption or Substitution by oxygen, 45 Sulfur, nitrogen, aralkyl, and C- alkenyl, X is carbon or The inventive latent foaming agent may be used in an Sulfur, Z is a Single bond or double bond, and a is 0 or 1, m amount within the range of about 0.05 to about 20 phr, such is 0-4, and n is 1-4. as about 1 to about 12 phr, desirably about 5 to about 10 phr, More Specific examples of the latent foaming agent 50 depending of course on the nature and identity of the matrix includes compounds comprising one or the other of the and the latent foaming agent. following structures II and III AS noted above, the matrix component may be Selected generally from curable monomers, oligomers and polymers, and thermoplastic oligomers and polymers. The curable 55 component may be functionalized either in the terminal portion, pendant portion, or both, with reactive groupS. Such as (meth)acrylate, alkoxides (attached to a silicone atom, or silylated alkoxides), aryloxides (attached to a silicone atom, or Sillylated aryloxides), Vinyls (attached to a silicone, or 60 silylated Vinyls), vinyl ethers, hydrides (attached to a sili cone atom, or Silicon hydrides), hydroxyl, isocyanate and epoxy, as well as combinations thereof. where R is is H, C, alkyl, with or without interruption or AS used herein, the terms (meth)acrylic and (meth) Substitution by oxygen, Sulfur, nitrogen, and aryl, R is C-2 acrylate are used synonymously with regard to the monomer alkyl, with or without interruption or Substitution by oxygen, 65 and monomer-containing component. The terms (meth) Sulfur, nitrogen, aralkyl and C-2 alkenyl, and m is 0-4, and acrylic and (meth)acrylate include acrylic, methacrylic, n is 1-4. acrylate and methacrylate. US 6,894,082 B2 7 8 The (meth)acrylate component may comprise one or more To cure Such (meth)acrylate component through exposure members Selected from a monomer represented by the to radiation in the electromagnetic spectrum, a photoinitiator formula: should be included, Such as benzoin and Substituted ben Zoins (Such as alkyl ester Substituted benzoins, like benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether), Michler's ketone, dialkoxyacetophenones Such as diethoxyacetophenone (“DEAP)), benzophenone and Sub Stituted be n Zophe none S, Such as N-methyl diethanolaminebenzophenone, acetophenone and Substi tuted acetophenones, and Xanthone and Substituted where G is hydrogen, halogen, or an alkyl having from 1 to Xanthones, Such as diethoxy Xanthone and chloro-thio 4 carbon atoms, R' has from 1 to 16 carbon atoms and is an Xanthone, azo-bisisobutyronitrile, and mixtures thereof. Vis alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkaryl, aralkyl, or ible light initiators include camphoquinone peroxyester ini aryl group, optionally Substituted or interrupted with Silane, tiators and non-fluorene-carboxylic acid peroxyesters. Silicon, oxygen, halogen, carbonyl, hydroxyl, ester, carboxy 15 In addition, the photoinitiators include those available lic acid, urea, urethane, carbamate, amine, amide, Sulfur, commercially from Ciba Specialty Chemicals, Brewster, Sulfonate, or Sulfone, New York under the “IRGACURE’ and “DAROCUR urethane acrylates or ureide acrylates represented by the trade names, specifically “ IRGA CURE” 184 formula: (1-hydroxycyclohexyl phenyl ketone), 907 (2-methyl-1-4- (methylthio)phenyl)-2-morpholino propan-1-one), 369 O O (2-benzyl-2-N,N-dimethylamino-1-(4-morpholinophenyl)- 1-butanone),500 (the combination of 1-hydroxy cyclohexyl phenyl ketone and benzophenone), 651 (2,2-dimethoxy-2- G phenyl acetophenone), 1700 the combination of bis(2,6- 25 dimethoxybenzoyl-2,4,4-trimethyl pentyl) phosphine oxide and 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 819 where bis(2,4,6-trimethyl benzoyl) phenyl phosphine oxide and G is hydrogen, halogen, or an alkyl having from 1 to 4 “DAROCUR” 1173 (2-hydroxy-2-methyl-1-phenyl-1- carbon atoms, propane) and 4265 (the combination of 2,4,6- R denotes a divalent aliphatic, cycloaliphatic, aromatic, trimethylbenzoyldiphenyl-phosphine oxide and 2-hydroxy or araliphatic group, bound through a carbon atom or 2-methyl-1-phenyl-propan-1-one); and the visible light carbon atoms thereof indicated at the -O-atom and blue photoinitiators, di-camphorduinone and "IRGA -X- atom or group; CURE 784DC. Of course, combinations of these materials X is -O-, -NH-, or -N(alkyl)-, in which the alkyl may also be employed herein. radical has from 1 to 8 carbon atoms, 35 Other photoinitiators useful herein include alkyl Z is 2 to 6; and pyruvates, Such as methyl, ethyl, propyl, and butyl R” is a Z-valent cycloaliphatic, aromatic, or araliphatic pyruvates, and aryl pyruvates, Such as phenyl, benzyl, and group bound through a carbon atom or carbon atoms appropriately Substituted derivatives thereof. thereof to the one or more NH groups; and Photoinitiators particularly well-suited for use herein a di- or tri-(meth)acrylate Selected from polyethylene 40 include ultraViolet photoinitiators, Such as 2,2-dimethoxy glycol di(meth) acrylates, bisphenol-A di(meth) 2-phenyl acetophenone (e.g., “IRGACURE” 651), and acrylates, tetrahydrofurane di(meth)acrylates, hex 2-hydroxy-2-methyl-1-phenyl-1-propane (e.g., anediol di(meth)acrylate, trimethylol propane tri(meth) “DAROCUR” 1173), bis(2,4,6-trimethyl benzoyl) phenyl acrylate, or combinations thereof. phosphine oxide (e.g., “IRGACURE” 819), and the Suitable polymerizable (meth)acrylate monomers include 45 ultraviolet/visible photoinitiator combination of bis(2,6- triethylene glycol dimethacrylate, tripropylene glycol dimethoxybenzoyl-2,4,4-trimethylpentyl) phosphine oxide diacrylate, tetraethylene glycol dimethacrylate, diethylene and 2-hydroxy-2-methyl-1-phenyl-propan-1-one (e.g., glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6- “IRGACURE” 1700), as well as the visible photoinitiator hexanediol dimethacrylate, pentaerythritol tetraacrylate, tri bis(m-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H methylol propane triacrylate, trimethylol propane 50 pyrrol-1-yl)phenyltitanium (e.g., “IRGACURE” 784DC). trime thacrylate, di-p enta erythritol Still other photoinitiators include hydrogen abstraction monohydroxypentaacrylate, pentaerythritol triacrylate, photoinitiators, provided that a hydrogen donor component bisphenol-A-ethoxylate dimethacrylate, trimethylolpropane is used as well. A number of hydrogen abstraction photo ethoxylate triacrylate, trimethylolpropane propoxylate initiators may be employed herein to provide the benefits triacrylate, and bisphenol-A-diepoxide dimethacrylate. 55 and advantages of the present invention to which reference Additionally, the (meth)acrylate monomers include poly is made above. Examples of Suitable hydrogen abstraction ethylene glycol di(meth)acrylates, bisphenol-A di(meth) photoinitiators for use herein include, but are not limited to, acrylates, tetrahydrofurane (meth)acrylates and di(meth) benzophenone, benzil (dibenzoyl), Xanthone, pentadione, acrylates, citronellyl acrylate and citronellyl methacrylate, thioxanthrenequinone (“TXAQ”), 2,3-butanedione hydroxypropyl (meth)acrylate, hexanediol di(meth)acrylate, 60 (diacetyl), phenanthrene quinone ("PAO”), ethylan trimethylol propane tri(meth)acrylate, tetrahydrodicyclo thraquinone (“EAQ”), 1,4-chrysenequinone, anthraquinone pentadienyl (meth)acrylate, ethoxylated trimethylol propane (“AQ”), camp hor quinone (“CO”), pyrene triacrylate, triethylene glycol acrylate, triethylene glycol (benzophenanthrene), benzanthrone and combinations methacrylate, and combinations thereof. thereof. Of course, (meth)acrylated Silicones may also be used, 65 Hydrogen donors useful in this regard ordinarily have one provided the Silicone backbone is not So large So as to or more labile hydrogens attached to a carbon, which is minimize the effect of (meth)acrylate when cure occurs. attached to a heteroatom, Such as oxygen, or to point of US 6,894,082 B2 9 10 unsaturation. A variety of Such materials may be used in the ethylhexanoate), “LUPERSOL” 80 (t-butyl present invention. For instance, ethers, alcohols and allylic peroxyisobutyrate), “LUPERSOL”. PMA(t-butyl peroxyma compounds are well Suited to donote hydrogen, particularly leic acid), “LUPERCO”. PMA-25 (t-butyl peroxymaleic where the ether and alcohol contain more than one Such acid), “LUPERSOL” 70 (t-butyl peroxyacetate), “LUPER group per molecule, and the allylic compound has more than SOL” 75-M (t-butyl peroxyacetate), LUPERSOL” 76-M one allylic hydrogen. (t-butyl peroxyacetate), “LUPERSOL” 555M60 (t-amyl In addition, it may be desirable to use cleavage photini peroxy-acetate), “LUPERSOL” KDB (di-t-butyl tiators in combination with the hydrogen abstraction pho diperoxyphthalate), “LUPERSOL” TBIC-M75 (t-butyl-o- toinitiator. isopropyl monoperoxycarbonate), “LUPEROX” 118 2.5- Generally, the amount of photoinitiator should be in the dimethyl-2,5-di(benzoylperoxy)hexane), “LUPERSOL” range of about 0.1% to about 10% by weight, such as about TBEC t-butyl-O-(2-ethylhexyl) monoperoxycarbonate), 2 to about 6% by weight. “LUPERSOL” TAEC t-amyl-o-(2-ethylhexyl) To cure Such (meth)acrylate component through exposure monoperoxycarbonate), “LUPEROX” 500R (dicumyl to elevated temperature conditions, a heat cure catalyst peroxide), “LUPEROX" 500T (dicumyl peroxide), should be included, Such as azo compounds and peroxides. 15 “LUPERCO" 500-40C (dicumyl peroxide), “LUPERCO” More Specifically, heat cure catalysts may be chosen from 500-40E (dicumyl peroxide), “LUPERCO" 500-SRK those available commercially from E.I. duPont and de (dicumyl peroxide), “LUPERSOL” 101 (2,5-dimethyl-2,5- Nemeurs, Wilmington, Del. under the tradenames di-(t-butylperoxy) hexane), “LUPERSOL”. 101-XL 2.5- “LUPERSOL”, “DELANOX-F", “ALPEROX-F", dimethyl-2,5-di-(t-butylperoxy) hexane), “LUPERCO' 101 “LUCIDOL”, “LUPERCO", and “LUPEROX". P20 2,5-dimethyl-2,5-di-(t-butylperoxy) hexane), Examples include “LUPERSOL” DDM-9 (mixtures of “LUPERSOL” 801 (t-butyl cumyl peroxide), “LUPERCO” peroxides and hydroperoxides), “LUPERSOL” DDM-30 801-XL (t-butyl cumyl peroxide), “LUPEROX” 802 bis(t- (mixtures of peroxides and hydroperoxides), “LUPERSOL” butylperoxy)diisopropylbenzene), “LUPERCO” 802-40KE DELTA-X-9 (mixtures of peroxides and hydroperoxides), bis(t-butylperoxy)diisopropylbenzene), “LUPERSOL” 130 “LUPERSOL” DHD-9 (mixtures of peroxides and 25 2,5-dimethyl-2,5-di-(t-butylperoxy) he Xyne-3, hydroperoxides), “LUPERSOL” DFR (mixtures of perox “LUPERCO" 130-XL 2,5-dimethyl-2,5-di-(t-butylperoxy) ides and hydroperoxides), “LUPERSOL” DSW-9 (mixtures hexyne-3), “LUPEROX” 2.5-2.5 (2,5-dihydro-peroxy-2,5- of peroxides and hydroperoxides), “LUPERSOL” 224 (2,4- dimethylhexane), “LUPERSOL” 230 n-butyl-4,4-di-(t- pentanedione peroxide), “LUPERSOL” 221 di(n-propyl) butylperoxy)valerate), “LUPERCO” 230-XL n-butyl-4.4- peroxydicarbonate), “LUPERSOL” 225 di(s-butyl) di-(t-butylperoxy)valerate), “LUPERSOL” 231 (1,1-di(t- peroxydicarbonate), “LUPERSOL” 225-M75 di(s-butyl) butylperoxy)-3,3,5-trimethyl cyclohexane), “LUPERCO” peroxydicarbonate), “LUPERSOL” 225-M60 di(s-butyl) 231-XL 1,1-di(t-butylperoxy) 3,3,5-trimethyl peroxydicarbonate), “LUPERSOL” 223 di(2-ethylhexyl) cyclohexane), “LUPERSOL” 231-P75 (1,1-di(t- peroxydicarbonate), “LUPERSOL” 223-M75 di(2- butylperoxy) 3,3,5-trimethyl cyclohexane), “LUPERCO” ethylhexyl)peroxydicarbonate), “LUPERSOL” 223-M40 di 35 231-SRL 1,1-di(t-butylperoxy)-3,3,5-trimethyl (2-ethylhexyl)peroxydicarbonate), “LUPERSOL” 219-M60 cyclohexane), “LUPERSOL” 331-80B 1,1-di(t- (diisononanoyl peroxide), “LUCIDOL” 98 (benzoyl butylperoxy)cyclohexane), “LUPERCO” 331-XL 1,1-di(t- peroxide), “LUCIDOL” 78 (benzoyl peroxide), “LUCI butylperoxy)cyclohexane), “LUPERSOL” 531-80B 1,1-di DOL” 70 (benzoyl peroxide), “LUPERCO” AFR-400 (t-amylperoxy)cyclohexane), “LUPERSOL” 531-80M 1,1- (benzoyl peroxide), “LUPERCO” AFR-250 (benzoyl 40 di(t-amylperoxy)cyclohexane), “LUPERSOL” 220-D50 peroxide), “LUPERCO” AFR-500 (benzoyl peroxide), 2,2-di(t-butylperoxy)butane), “LUPERSOL” 233-M75 “LUPERCO” ANS (benzoyl peroxide), “LUPERCO” ethyl-3,3-di(t-butylperoxy)butyrate), “LUPERCO' 233-XL ANS-P (benzoyl peroxide), “LUPERCO” ATC (benzoyl ethyl-3,3-di(t-butylperoxy)butyrate), “LUPERSOL” P-31 peroxide), “LUPERCO” AST (benzoyl peroxide), 2,2-di-(t-amylperoxy)propane), “LUPERSOL” P-332,2- “LUPERCO” AA (benzoyl peroxide), “LUPERCO” ACP 45 di-(t-amylperoxy)propanel, and “LUPERSOL” 553-M75 (benzoyl peroxide), “LUPERSOL” 188M75 (cumylperoxy ethyl 3,3-di(t-amylperoxy)butyrate). neodecanoate), “LUPERSOL 688T50 (1,1-dimethyl-3- Other heat cure catalysts include those available commer hydroxy-butyl peroxy neoheptanoate), “LUPERSOL” cially from DuPont under the “VAZO' tradename, such as 688 M5 O (1,1-dimethyl-3-hydroxy-butyl “VAZO' 64 (azobis-isobutyrile nitrile), “VAZO” 67 (butane peroxyneoheptanoate), “LUPERSOL” 28.8M75 (cumyl 50 nitrile, 2-methyl, 2,2'-azobis) and “VAZO' 88 (cyclohexane peroxy neoheptanoate), “LUPERSOL” 546 M75 carbonitrile, 1,1'-azobis). (t-amylperoxy neodecanoate), “LUPERSOL” 10 Generally, the amount of heat cure catalyst Should be in (t-butylperoxy neodecanoate), “LUPERSOL” 10M75 the range of about 0.1% to about 10% by weight, such as (t-butylperoxy neodecanoate), “LUPERSOL” 554M50 about 2 to about 6% by weight. (t-amylperoxypivalate), “LUPERSOL” 554M 75 55 Anaerobic cure-inducing compositions useful in (t-amyl peroxy piva late), “LUPER SOL” 11 anaerobically-curable versions of the foamable composi (t-butylperoxypivalate), “LUPERSOL” 665T50 (1-1- tions include a variety of components, Such as amines dimethyl-3-hydroxy-butylperoxy-2-ethylhexanoate), (including amine oxides, Sulfonamides and triazines). A “LUPERSOL” 665M50 (1-1-dimethyl-3-hydroxy desirable composition to induce cure includes Saccharin, butylperoxy-2-ethylhexanoate), “LUPERSOL” 256 2.5- 60 toluidenes, such as N,N-diethyl-p-toluidene and N,N- dimethyl-2,5-di(2-ethylhexanoyl peroxy)hexane), “LUPER dimethyl-o-toluidene, acetyl phenylhydrazine (“APH'), and SOL” 575 (t-amylperoxy-2-ethyl-hexanoate), maleic acid. Of course, other materials known to induce “LUPERSOL” 575P75 (t-amylperoxy-2-ethyl-hexanoate), anaerobic cure may also be included or Substituted therefor. “LUPERSOL” 575M75 (t-amylperoxy-2-ethyl-hexanoate), See e.g., U.S. Pat. Nos. 3,218,305 (Krieble), 4,180,640 t-BUTYL PER O CTO ATE (t-butylperoxy-2- 65 (Melody), 4,287,330 (Rich) and 4,321,349 (Rich). ethylhexanoate), “LUPERSOL”. PMS (t-butylperoxy-2- Quinones, Such as napthoguinone and anthraquinone, may ethylhexanoate), “LUPERSOL” PDO (t-butylperoxy-2- also be included to Scavenge free radicals that may form. In US 6,894,082 B2 11 12 addition, free-radical initiators, free-radical accelerators, anhydride (“HHPA") and methylhexahydrophthalic anhy inhibitors of free-radical generation, as well as metal dride (“MHHPA”) (commercially available from Lindau catalysts, may also be added. Chemicals, Inc., Columbia, S.C., used individually or as a Generally, the amount of anaerobic cure-inducing com combination, which combination is available under the trade position should be in the range of about 0.1% to about 10% designation “LINDRIDE'' 62C), 5-(2,5-dioxotetrahydrol)-3- by weight, such as about 2 to about 6% by weight. methyl-3-cyclohexene-1,2-dicarboxylic anhydride AS the epoxy, examples include C-C alkyl glycidyl (commercially available from ChrisKev Co., Leewood, ethers, C-C alkyl- and alkenyl-glycidyl esters; C1-Cs Kans. under the trade designation B-4400) and nadic methyl alkyl-, mono- and poly-phenol glycidyl ethers, polyglycidyl anhydride. ethers of pyrocatechol, resorcinol, hydroquinone, 4,4'- Of course, combinations of these anhydryde compounds dihydroxydiphenyl methane (or bisphenol F), 4,4'- are also desirable for use in the compositions of the present dihydroxy-3,3'-dimethyldiphenyl methane, 4,4'- invention. dihydroxydiphenyl dimethyl methane (or bisphenol A), 4,4'- dihydroxydiphenyl methyl methane, 4,4'-dihydroxydiphenyl The nitrogen-containing compounds include aza com cyclohexane, 4,4'-dihydroxy-3,3'-dimethyldiphenyl pounds (Such as di-aza compounds or tri-aza compounds), propane, 4,4'dihydroxydiphenyl Sulfone, and tris(4- 15 examples of which include: hydroxyphyenyl)methane; polyglycidyl ethers of the chlo N rination and bromination products of the above-mentioned 21 diphenols, polyglycidyl ethers of novolacs, polyglycidyl ethers of diphenols obtained by esterifying ethers of diphe nols obtained by esterifying Salts of an aromatic hydrocar CO boxylic acid with a dihaloalkane or dihalogen dialkyl ether; polyglycidyl ethers of polyphenols obtained by condensing 1,5-Diazabicyclo4.3.0non-5-ene phenols and long-chain halogen paraffins containing at least two halogen atoms; N,N'-diglycidyl-aniline; N,N'-dimethyl N N,N'-diglycidyl-4,4'diaminodiphenyl methane; N.N,N',N'- 25 21 tetraglycidyl-4,4'diaminodiphenyl methane; N,N'- diglycidyl-4-aminophenyl glycidyl ether; N,N,N',N'- tetraglycidyl-1,3-propylene bis-4-aminobenzoate; phenol novolac epoxy resin; creSol novolac epoxy resin; and com binations thereof. 1,8-Diazabicyclo5.4.0]undec-5-ene (DBU Among the commercially available epoxy resins Suitable for use herein are polyglycidyl derivatives of phenolic compounds, Such as those available under the tradenames EPON 828, EPON 1001, EPON 1009, and EPON 1031, 35 CO from Resolution Performance Products LLC; DER 331, DER 332, DER 334, and DER542 from Dow Chemical Co.; H GY285 from Vantico, Inc., Brewster, N.Y.; and BREN-S from Nippon Kayaku, Japan. Other Suitable epoxy resins 1,5,7-Triazabicyclo4.4.0dec-5-ene include polyepoxides prepared from polyols and the like and and the bicyclo mono- and di-aza compounds: polyglycidyl derivatives of phenol-formaldehyde novolacs, 40 the latter of which are available commercially under the tradenames DEN 431, DEN 438, and DEN 439 from Dow Chemical Company. CreSol analogs are also available com mercially ECN 1235, ECN 1273, and ECN 1299 from Ciba (G Specialty Chemicals, Inc. SU-8 is a bisphenol A-type epoxy 45 novolac available from Resolution Performance Products Quinuclidine LLC. Polyglycidyl adducts of amines, aminoalcohols and N polycarboxylic acids are also useful in this invention, com mercially available resins of which include GLYAMINE ()N 135, GLYAMINE 125, and GLYAMINE 115 from F.I.C. 50 Corporation; ARALDITE MY-720, ARALDITE MY-721, ARALDITE 0500, and ARALDITE 0510 from Ciba Spe 1,4-Diazabicyclo2.2.2]octane cialty Chemicals, Inc. and PGA-X and PGA-C from the Examples of the amine compounds include aliphatic Sherwin-Williams Co. And of course combinations of the polyamines, Such as diethylenetriamine, triethylenetetra different epoxy resins are also useful herein. 55 mine and diethylaminopropylamine, aromatic polyamines, Other appropriate epoxy resins Suitable for use as the Such as m-Xylenediamine and diaminodiphenylamine; and curable matrix component include cycloaliphatic ones, Such alicyclic polyamines, Such as isophoronediamine and men as those available commercially from Dow under the ERL thenediamine. trade designation like ERL-4221. Of course, combinations of these amine compounds are In addition, when epoxy functionality is present on the 60 also desirable for use in the compositions of the present curable matrix component, desirable curing agents include invention. an anhydride component, a nitrogen-containing component, Examples of amide compounds include cyano Such as an aza compound, an amine compound, an amide functionalized amides, Such as dicyandiamide. compound, and an imidazole compound, and combinations The imidazole compounds may be chosen from thereof. 65 imidazole, isoimidazole, and Substituted imidazoles-Such Appropriate anhydride compounds for use herein include as alkyl-substituted imidazoles (e.g., 2-methyl imidazole, mono- and poly-anhydrides, Such as hexahydrophthalic 2-ethyl-4-methylimidazole, 2,4-dimethylimidazole, US 6,894,082 B2 13 14 butylimidazole, 2-heptadecenyl-4-methylimidazole, poly(decamethylene 4-octendioate), with a melting point of 2-undecenylimidazole, 1-vinyl-2-methylimidazole, 2-n- 53 C., poly(butylvinyl ether), with a melting point of 64 he pta de cylimidazole, 2- unde cylimidazole, C., poly(decamethylene oxide), with a melting point of 79 2-heptadecylimidazole, 1-benzyl-2-methylimidazole, 1- propyl-2-methylimidazole, 1 -cyano ethyl-2- C., poly(hexamethylene sulfide), with a melting point of 90° methylimidazole, 1-cyanoethyl-1-cyano ethyl-2- C., and poly(ethylene amine), with a melting point of 58 C. undecylimidazole, 1-cyanoethyl-2-phenylimidazole, For additional examples, see R. Miller, Polymer Handbook, 1-guanaminoethyl-2-methylimidazole and addition products chap. 4,4" ed., J. Bandrup et al., eds., J. Wiley & Sons, New of an imidazole and trimellitic acid, 2-n-heptadecyl-4- York (1999). methylimidazole and the like, generally where each alkyl 1O The latent foamable composition of the present invention Substituent contains up to about 17 carbon atoms and desirably up to about 6 carbon atoms), and aryl-substituted may further include Stabilizers, accelerators, fillers, imidazoles e.g., phenylimidazole, benzylimidazole, thickeners, Viscosity modifiers, adhesion promoters, 2-methyl-4,5-diphenylimidazole, 2,3,5-triphenylimidazole, inhibitors, thixotropy conferring agents, tougheners, anti 2-Styrylimidazole, 1-(dodecyl benzyl)-2-methylimidazole, 15 Oxidizing agents, anti-reducing agents, and combinations 2-(2-hydroxyl-4-t-butylphenyl)-4,5-diphenylimidazole, thereof. These optional additives are used in an amount that 2-(2-methoxyphenyl)-4,5-diphenylimidazole, 2-(3- do not significantly adversely affect the polymerization hydroxyphenyl)-4,5-diphenylimidazole, 2-(p- process or the desired properties of the cured composition. dimethylaminophenyl)-4, 5-diphenylimidazole, 2-(2- hydroxyphenyl)-4,5-diphenylimidazole, di(4,5-diphenyl-2- With respect to formulating latent foam able imidazole)-benzene-1,4,2-naphthyl-4,5-diphenylimidazole, compositions, generally the components may be introduced 1-benzyl-2-methylimidazole, 2-p-methoxystyrylimidazole, to one another in any convenient order. Alternatively, it may and the like, generally where each aryl Substituent contains be desirable to prepare a premix of the latent foaming agent up to about 10 carbon atoms and desirably up to about 8 and the initiator component. In this way, a ready made carbon atoms. 25 premix of those components may be added to the curable or Examples of commercial imidazole compounds are avail thermoplastic component of the formulation to allow for a able from Air Products, Allentown, Pa.. under the trade quick and easy one-part formulation prior to dispensing, designation “CUREZOL” 1B2MZ and from Synthron, Inc., foaming and curing thereof. Morganton, N.C. under the trade designation “ACTIRON” NX-60. For packaging and dispensing purposes, it may be desir Examples of the modified imidazole compounds include able for latent foamable compositions in accordance with the imidazole adducts formed by the addition of an imidazole present invention to be relatively fluid and flowable. Varia compound to an epoxy compound. For instance, "AJI tions in the Viscosity thereof may also be desirable in certain CURE” PN-23, commercially available from Ajinomoto applications and may be readily achieved through routine Co., Inc., Tokyo, Japan, is believed to be an adduct of EPON 35 changes in formulation, the precise changes being left to 828 (bisphenol-A-type epoxy resin, epoxy equivalent those perSons of ordinary skill in the art. 184-194, commercially available from Resolution Perfor mance Products LLC), 2-ethyl-4-methylimidazole and The following examples describe the preparation and use phthalic anhydride. Others commercially available ones of latent curable compositions of the present invention. from Ajinomoto include “AMICURE" MY-24, “AMIC 40 These examples are presented for the purpose of further URE GG-216 and “AMICURE ATU CARBAMATE. In illustrating and explaining the invention, and are not to be addition, “NOVACURE” HX-3722 (an imidazole/bisphenol taken as limiting the Scope of the invention. A epoxy adduct dispersed in bisphenol A epoxy) and “NOVACURE” HX-3921 HP, commercially available from EXAMPLES Asahi-Ciba, Ltd., may also be used. 45 Of course, combinations of these imidazole compounds are also desirable for use in the compositions of the present All Starting materials and Solvents were all purchased invention. from the Aldrich Chemical Company, and were used without The curing agent for the curable matrix component with further purification. epoxy functionality present may be used in an amount of 50 from about 3 to about 100 weight percent, based on the Nuclear Magnetic Resonance (H NMR and 'C NMR) weight of the curable aromatic resin component, depending analyses were performed on a Varian 300 Hz. Gemini Spec of course on the type and identity of the curing agent tophotometer. Infrared (“IR”) spectra were obtained neat on component. an ATI Mattson Genesis series FTIR spectrophotomer or a Notwithstanding that which is described above, the 55 Perkin-Elmer Spectrum One FT-IR spectrophotomer. Pho amount of the initiator or catalyst will depend on the nature todifferential scanning calorimetry (“PhotoDSC) analyses and identity of the curable matrix component, as well. were performed on a TA Instruments 2920 Differential Examples of the thermoplastic oligomers and polymers Scanning Calorimeter, equipped with a Photocalorimetry that may benefit from the photo-induced foaming agent Attachment. Thermogravimetric analysis (“TGA) data was include those with a melting point of less than or equal about 60 acquired on a TA Instruments 2950 Thermogravimetric 100° C. For instance poly(olefins), poly(dienes), poly Analyzer. (peptides), poly(esters), poly(ethers), poly(oxides), poly (Sulfides), and poly(amines). More specific examples of Such In general, preparation of the inventive latent foaming thermoplastic oligomers and polymers include Syndiotactic agents involved reaction of an aliphatic acid chloride with polybutatene, with a melting point of 45 C., alpha 65 the Sodium Salt of 2-mercaptopyridine-1-oxide in toluene, polyisoprene, with a melting point of 80° C., poly(2-butyl with dimethylaminopyridine (“DMAP) as a catalyst to 2-methyl-beta-alanine), with a melting point of 72 C., form the O-acylthiohyroXamate, 1, as Seen in eq. 2. US 6,894,082 B2 16 170, 138,137, 134,113, 29,8; IR (KBr): 3098, 2985, 1806, eq. 2 1607, 1527, 1449, 1412, 1134, 1050, 846, 750 cm. N Octanoyl Thiohydroxamate, 5 O -- DMAP Yellow liquid; Yield=18.8 g (74%); H NMR (CDC1): 8 N se P -estoluene 7.7 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 2.7 Cl R (m, 2, COCH), 1.1–1.9 (m, 10, CH), 0.9 (m, 3, CH); 'C OH NMR (CDC1): 8 176, 170, 138,137, 134,113,32, 29.2, 29, 2-mercaptopyridine-1-Oxide, 24, 22, 16; IR (neat): 3092, 2924, 1810, 1607, 1527, 1448, sodium salt 1411, 1132, 1061, 751 cm. 1O rs Palmitoyl Thiohydroxamate, 6 S Yellow solid; Yield=21.6 g (61%); H NMR (CDC1): 8 7.6 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 2.7 O 15 (m, 2, COCH), 1.1–1.9 (m, 22, CH), 0.9 (m, 3, CH); 'C NY NMR (CDC1): 8 176, 170,139.2, 139, 134, 113, 32.2, 32, R 30, 39.8, 39.6, 24, 22, 15; IR (KBr): 3090, 2917,2849, 1809, o-Acylthiohydroxamate, 1 1606, 1528, 1450, 1409, 1136, 1068, 1056, 890, 736 cm. Oleoyl Thiohydroxamate, 7 Six o-acylthiohydroxamates, 3-8, within the scope of this invention were prepared by this method, details for which Amber liquid; Yield=35.7g (94%); H NMR (CDC1): 8 are given below. 7.6 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 5.4 (m, 2, RCH=CHR), 2.7 (m, 2, COCH), 2.0 (bris, 4, 25 C=C-CH-), 1.1–1.9 (m, 22, CH), 0.9 (s, 3, CH); 'C NMR (CDC1): 8 176, 170,139.2, 139,134, 130, 129.6, 113, 32.2, 32, multiple peaks at 30+0.5, 28, 25, 23, 15; IR (KBr): 3004, 2924, 2853, 1808, 1608, 1526, 1448, 1411, 1134, rs 1056, 731 cm. S Cyclopentanoyl Thiohydroxamate, 8 O Amber liquid; Yield=18.3 g (87%); H NMR (CDC1) & 7.6 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 3.1 (m, 2, COCH), 1.6-2.4 (m, 8, CH); 'C NMR (CDC1): 8 R 176, 172,139.2, 139,134,113,42, 30, 26; IR (neat): 3091, 35 3, Acetyl, R = -CH 2960, 2871, 1800, 1607, 1526, 1448, 1410, 1178, 1134, 4. Propanoyl, R = -CHCH 1055, 922,838, 745 cm. 5, Octanoyl, R = -(CH),CH TGA Analysis of Latent Foaming Agent 6, Palmitoyl, R = -(CH2)CH (PTH) 7, Oleyol, R = -(CH2)CH=CH(CH),CH The O-acylthiohydroxamates were evaluated by thermo 8, Cyclopentanoyl, R = -CH gravimetric analysis (“TGA) to determine their relative 40 thermal stability. A 5-10 mg sample of the O-acylthiohydroxamate was placed in the TGA instrument General Synthetic Procedure and was heated at 20° C./minute to a temperature of 500 C. To a 500 mL flask, equipped with a mechanical Stirrer, an TGA analysis for acetyl thiohydroxamate, 3, palmitoyl addition funnel, and a nitrogen inlet, 2-mercaptopyridine-1- thiohydroxamate, 6, and oleoyl thiohydroxamate, 7, are oxide sodium salt (17.9 g, 120 mmol) and DMAP (0.12 g, 45 shown in FIG. 1, which indicates decomposition beginning 1 mmol) were added to CHCl (300 mL). After stirring for at temperatures about 100° C. 15 minutes, the acid chloride (100 mmol) was added slowly to the reaction mixture, which becomes bright yellow in Latent Foamable Curable Compositions color. The reaction mixture was Stirred under nitrogen for Photo-induced foamable compositions were prepared 1-2 hrs. Solid impurities were filtered out of the reaction 50 from the noted components in the respective amounts, as mixture. The organic layer was washed twice each with 200 shown in Table 1. mL of 1M aq. KHSO, 200 mL of 5% aq. NaHCO, and 200 mL of water. The organic layer was then dried (K-CO), TABLE 1. filtered, and Solvent removed under reduced pressure. The Material phr products were dried in a vacuum oven overnight at a 55 temperature of 40 C. under best vacuum. Urethane/Acrylate Block Resin 75 N,N-Dimethylacrylamide 25 Product Appearance, Yield, and Spectral Data Acetyl Darocure 1173 1. Thiohydroxamate, 3 o-Acyl Thiohydroxamate 0-8 Yellow solid; Yield=10 g (64%); H NMR (CDC1): 8 7.8 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 2.5 (s, 3, 60 CH); C NMR (CDC1): 8 176, 167, 138.2, 138,134,113, Production of a Photo-Induced Foam 19; IR (neat): 3065,3020, 1797, 1607, 1416, 1146,857,751 At concentrations of 2 phr or greater, the generation of a cm. foam from the urethane (meth)acrylate-based curable com Propionyl Thiohydroxamate, 4 position was observed concurrent with exposure to UV Yellow liquid; Yield=7.8 g (42%); H NMR (CDC1): 8 65 radiation, within a LOCTITE ZETA7215 UV Curing Cam 7.8 (m, 2, =CH), 7.2 (m, 1, =CH), 6.6 (m, 1, =CH), 2.5 ber. A bead of the composition was dispensed on a Substrate (m, 2, COCH), 1.2 (m, 3, CH); C NMR (CDC1): 8 176, and placed in the curing chamber for Subsequent UV expo US 6,894,082 B2 17 Sure. Foaming data for the composition with different con centrations of palmitoyl thiohydroxamate (“PTH'), 6, is TABLE 5-continued given in Table 2. No. Additive/Peroxide 80° C. 110° C. 140° C. TABLE 2 6. 8% PTH/2% Luperox TBEC X foam foam 7. 8% PTH/2% Luperox DC X X foam Phr of PTH % Increase in Height 8. 8% PTH/2% Luperox 101 X X foam O O X = no foam formation 0.5 O O.75 O Foaming was observed for Sample Nos. 3–8, as indicated, 1.O O 2.O 8 with a doubling in height as compared to the uncured 3.0 84 material. The temperatures at which the foams were gener 4.0 113 ated were consistent with the peroxide initiator one hour half-life decomposition temperatures. The addition of PTH, 6, produces a dry, closed-cell foam, 15 The control formulations (Sample Nos. 1 and 2) contain which was generated with UV radiation at intensities as low ing no additives and 8% PTH without any peroxide initiator, as 50 mW/cm°. did not generate a foam, even at a temperature of 140 C. Production of Heat-Induced Foam Evaluation of Photocure for Formulations with Latent Formulations, which contained a heat cure catalyst, Such Foaming Agent but Without Separate Photoinitiator as a peroxide, as the initiator instead of a photoinitiator as Set The formulation with 8% PTH alone, without added forth in Table 1 above, were prepared using peroxide ini photoinitiator or peroxide, was exposed to UV radiation for 20 Seconds. A cured, foamed polymer formed, with a tiators with one hour half-life decomposition temperatures decreased cure-through-depth, as compared to the ranging from 80 C. to 140 C., as shown below in Table 3. formulation, which contained a photoinitiator. 25 What is claimed is: TABLE 3 1. A latent foamable composition, comprising: Peroxide Chemical Name T2 1 hour (C.) (a) a matrix component; and Luperox LP Lauroyl Peroxide 81 (b) a latent foaming agent, wherein upon exposure to Luperox A98 Benzoyl Peroxide 92 conditions Sufficient to cause the latent foaming agent Luperox P t-Butyl Peroxybenzoate 121 to foam, at a concentration of 2 phr the composition is Luperox TBEC t-Butylperoxy 2- 125 capable of increasing in size in at least one direction by ethylhexyl Carbonate Luperox DC Dicumyl Peroxide 137 8%, Luperox 101 2.5-Bis(t-butylperoxy)- 140 2,5-dimethyl hexane 35

Heat-induced foamable compositions were prepared from R2 the noted components in the respective amounts, as shown in Table 4. 40 S TABLE 4 Material Phr wherein R' is H, C, alkyl, with or without interruption Urethane/Acrylate Block Resin 75 or Substitution by oxygen, Sulfur, and nitrogen, R is N,N-Dimethylacrylamide 25 C. alkyl, with or without interruption or Substitution Palmitoyl thiohydroxamate (PTH) 8 45 by oxygen, Sulfur, nitrogen, aralkyl or Calkenyl, X Peroxide 2 is carbon or Sulfur, Z is a single bond or double bond, a is 0 or 1, m is 0-4, and n is 1-4. When the peroxide initiator was added, each formulation 2. A latent foamable curable composition, comprising: was mixed with care to prevent the generation of heat during (a) a curable matrix component; and the mixing process. Approximately 7 grams of each formu 50 (b) a latent foaming agent, wherein upon exposure to lation was weighed into three aluminum pans, and a Sample conditions Sufficient to cause the latent foaming agent for each thiohydroxamate was heated for one hour at a to foam, at a concentration of 2 phr the composition is temperature of 80 C., at a temperature of 110° C., and at a capable of increasing in size in at least one direction by temperature of 140 C. Formulations containing no additives 8%, (Table 5, Sample No. 1) and 8% PTH alone (Table 5, Sample 55 No. 2), were used as controls. The data from these experi ments are Summarized in Table 5. R2 TABLE 5 60 No. Additive/Peroxide 80° C. 110° C. 140° C. S 1. None X X X 2. 8% PTH alone X X X 3. 8% PTH/2% Luperox LP foam foam foam 4. 8% PTH/2% Luperox A98 foam foam foam 65 wherein R is H, C alkyl, with or without interruption 5. 8% PTH/2% Luperox P X foam foam or Substitution by oxygen, Sulfur, and nitrogen, R is C. alkyl, with or without interruption or Substitution US 6,894,082 B2 19 20 by oxygen, Sulfur, nitrogen, aralkyl or C-2 alkenyl, X 9. The composition of claim 1, wherein the matrix com is carbon or Sulfur, Z is a Single bond or double bond, ponent is a (meth)acrylate component comprising one or a is 0 or 1, m is 0-4, and n is 1-4. more members Selected from the group consisting of 3. A latent foamable curable composition, comprising: (a) a curable component; a monomer represented by the formula: (b) an initiator component; and (c) a latent foaming agent, wherein upon exposure to conditions Sufficient to cause the latent foaming agent to foam, at a concentration of 2 phr the composition is capable of increasing in size in at least one direction by 8%, wherein G is hydrogen, halogen, or an alkyl having from 1 to 4 carbon atoms, R' has from 1 to 16 carbon atoms and is 15 an alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkaryl, aralkyl, R2 or aryl group, optionally Substituted or interrupted with Silane, Silicon, oxygen, halogen, carbonyl, hydroxyl, ester, carboxylic acid, urea, urethane, carbamate, amine, amide, S Sulfur, Sulfonate, or Sulfone, a di- or tri-(meth)acrylate comprising polyethylene glycol wherein R is H, C, alkyl, with or without interruption di(meth)acrylates, bisphenol-A di(meth)acrylates, tet or Substitution by oxygen, Sulfur, and nitrogen, R is rahydrofurane di(meth)acrylates, hexanediol di(meth) C. alkyl, with or without interruption or Substitution by oxygen, Sulfur, nitrogen, aralkyl or Calkenyl, X acrylate, trimethylol propane tri(meth)acrylate, or com is carbon or Sulfur, Z is a Single bond or double bond, 25 binations thereof; a is 0 or 1, m is 0-4, and n is 1-4. urethane (meth)acrylates or ureide (meth)acrylates repre 4. A latent foamable curable composition, comprising: sented by the formula: (a) a curable component; and (b) a latent foaming agent, provided that (meth)acrylate is O O not the only component of the curable matrix component,

35 wherein G is hydrogen, halogen, or an alkyl having from R2 1 to 4 carbon atoms, R denotes a divalent aliphatic, cycloaliphatic, aromatic, S or araliphatic group, bound through a carbon atom or 40 carbon atoms thereof indicated at the -O-atom and -X- atom or group; wherein R is H, C, alkyl, with or without interruption or Substitution by oxygen, Sulfur, and nitrogen, R is C-2 X is -O-, -NH-, or -N(alkyl)-, in which the alkyl alkyl, with or without interruption or Substitution by oxygen, radical has from 1 to 8 carbon atoms, Sulfur, nitrogen, aralkyl or C-2 alkenyl, X is carbon or 45 Z is 2 to 6; and Sulfur, Z is a Single bond or double bond, a is 0 or 1, m is R’ is a Z-valent cycloaliphatic, aromatic, or araliphatic 0-4, and n is 1-4. group bound through a carbon atom or carbon atoms 5. The composition of claim 1, wherein the matrix com thereof to the one or more NH groups. ponent is functionalized with one or more groups Selected 10. The composition of claim 1, wherein the latent foam from the group consisting of (meth)acrylate, silyl alkoxide, 50 ing agent comprises the following Structure silyl aryloxide, Sillyl vinyl, Vinyl ether, Silicon hydride, hydroxyl, isocyanate and epoxy. 6. The composition of claim 2, wherein the curable matrix (R) component is functionalized with one or more groups Selected from the group consisting of (meth)acrylate, silyl 55 alkoxide, Silyl aryloxide, Silyl vinyl, vinyl ether, Silicon hydride, hydroxyl, isocyanate and epoxy. 7. The composition of claim 3, wherein the curable component is functionalized with one or more groups Selected from the group consisting of (meth)acrylate, silyl 60 alkoxide, Silyl aryloxide, Silyl vinyl, vinyl ether, Silicon wherein R is H, C, alkyl, with or without interruption or hydride, hydroxyl, isocyanate and epoxy. Substitution by oxygen, Sulfur, and nitrogen, or R is C, 8. The composition of claim 4, wherein the curable alkyl, with or without interruption or Substitution by Oxygen, component is functionalized with one or more groups Sulfur, nitrogen, aralkyl or C-2 alkenyl, m is 0-4, and n is Selected from the group consisting of (meth)acrylate, silyl 65 1-4. alkoxide, Silyl aryloxide, Silyl vinyl, vinyl ether, Silicon 11. The composition of claim 1, wherein the latent foam hydride, hydroxyl, isocyanate and epoxy. ing agent comprises the following Structure US 6,894,082 B2 21 22 tougheners, anti-oxidizing agents, anti-reducing agents, and combinations thereof. (R'), 19. A method of making a foamable composition com prising the steps of / 5 providing a matrix component; R2 y providing a latent foaming agent, wherein the latent O S n' foaming agent is embraced by the following structure wherein R is H, C, alkyl, with or without interruption or substitution by oxygen, sulfur, and nitrogen, R is C-2, alkyl, with or without interruption or Substitution by oxygen, R2 sulfur, nitrogen, aralkyl or C-2 alkenyl, m' is 0-2, and n' is 1-4. 12. The composition of claim 1, wherein the matrix 15 S component is a member selected from the group consisting of the thermoplastic oligomers and polymers. 13. The composition of claim 12, wherein the matrix wherein R is H, C alkyl, with or without interruption or component has a melting point of less than or equal to about substitution by oxygen, Sulfur, and nitrogen, R is C1-24 100° C. alkyl, with or without interruption or Substitution by Oxygen, 14. The composition of claim 12, wherein the matrix sulfur, nitrogen, aralkyl or C-2 alkenyl, X is carbon or 1, component is a member selected from the group consisting m is 0-4, and n is 1-4; and of poly(olefins), poly(dienes), poly(peptides), poly(esters), mixing together the matrix component and the latent poly(ethers), poly(oxides), poly(Sulfides), and poly(amines). foaming agent to form the foamable composition. 15. The composition of claim 12, wherein the matrix 25 20. A method of making a foamed composition compris component is a member selected from the group consisting ing the steps of of syndiotactic polybutatene, with a melting point of 45 C., providing the composition of claim 1; and alpha-polyisoprene, with a melting point of 80 C., poly(2- exposing the composition to conditions Sufficient to foam butyl-2-methyl-beta-alanine), with a melting point of 72°C., the composition. poly(decamethylene 4-octendioate), with a melting point of 21. A method of assembling articles comprising the Steps 53° C., poly(butylvinyl ether), with a melting point of 64 C., poly(decamethylene oxide), with a melting point of 79 of C., poly(hexamethylene sulfide), with a melting point of 90° providing a first part with a Surface; C., and poly(ethylene amine), with a melting point of 58 C. dispensing onto at least a portion of the Surface of the part 16. The composition of claim 1, wherein the latent foam 35 the composition of claim 1; ing agent is a member selected from the group consisting of providing a second part with a Surface and joining the acetyl thiohydroxamate, propionyl thiohydroxamate, surface of the second part with the composition coated octanoyl thiohydroxamate, palmitoyl thiohydroxamate, ole surface of the first part to form an assembly; and oyl thiohydroxamate, cyclopentanoyl thiohydroxamate, and exposing the assembly to conditions Sufficient to foam the combinations thereof. 40 composition. 17. The composition of claim 1, wherein the latent foam 22. The method of claim 20, wherein conditions Sufficient ing agent is a member selected from the group consisting of to foam the composition include exposure to radiation in the O-esters of 4-methyl-N-hydroxy thiazole thione, electromagnetic spectrum. 3-palmitoyl-4-phenylthiazolethione, 3,3-diphenylpropionyl 23. The method of claim 21, wherein conditions Sufficient thiazolethione, palmitoyl thiazolethione, and combinations 45 to foam the composition include exposure to radiation in the thereof. electromagnetic spectrum. 18. The composition of claim 1, further comprising a 24. A foamed composition of claim 1. member selected from the group consisting of stabilizers, 25. A cured foamed composition of claim 2. accelerators, fillers, thickeners, Viscosity modifiers, adhe sion promoters, inhibitors, thixotrophy conferring agents, ck ck ck ck ck