United States Patent (19) (11) 4,161,571 Yasui et al. 45 Jul. 17, 1979

(54) PROCESS FOR PRODUCTION OF THE 4,080,493 3/1978 Yasui et al...... 260/879 MALE CANHYDRDE ADDUCT OF A 4,082,817 4/1978 Imaizumi et al...... 526/46 LIQUID POLYMER 4,091,198 5/1978 Smith ...... 526/56 75 Inventors: Seimei Yasui, Takarazuka; Takao FOREIGN PATENT DOCUMENTS Oshima, Sonehigashi, both of Japan 2262677 2/1975 France ...... 526/56 73) Assignee: Sumitomo Chemical Company, 44-1989 1/1969 Japan ...... 526/56 Limited, Osaka, Japan Primary Examiner-William F. Hamrock Attorney, Agent, or Firm-Birch, Stewart, Kolasch and 21 Appl. No.: 843,311 Birch 22 Filed: Oct. 18, 1977 57 ABSTRACT Related U.S. Application Data A process for production of the maleic anhydride ad duct of a liquid polymer having a maleic anhydride 62 Division of Ser. No. 733,914, Oct. 19, 1976, Pat, No. addition amount of 2 to 70% by weight, which com 4,080,493. prises reacting a liquid polymer having a molecular 51 Int. C.’...... CO8F 8/46 weight of 150 to 5,000 and a viscosity of 2 to 50,000 cp (52) U.S. C...... 526/90; 526/192; at 30 C. in the presence of at least one compound, as a 526/209; 526/213; 526/193; 526/195; 526/226; gelation inhibitor, selected from the group consisting of 526/233; 526/237; 526/238; 526/272; 525/285; imidazoles, thiazoles, metallic salts of mercapto 525/249; 525/251; 525/255; 525/245; 525/248 thiazoles, urea derivatives, naphthylamines, nitrosa (58) Field of Search ...... 526/56, 46, 48.1, 48.2, mines, iron, iron compounds and specific halogen com 526/24, 27, 40, 47; 260/879, 880 R pounds, said liquid polymer being selected from the (56) References Cited group consisting of liquid polybutadienes, liquid poly U.S. PATENT DOCUMENTS isoprenes and liquid copolymers comprising units of butadiene or isoprene and units of at least one com 2,388,477 11/1945 Fryling ...... 526/205 2,388,514 11/1945 Zwicker et al. .... 526/205 pound selected from the group consisting of other diole 3,546,184 12/1970 Heidel et al...... 526/56 fins, olefins and aromatic vinyl compounds. 3,778,418 12/1973 Nakayama ...... 526/56 3,937,677 2/1976 Broecker et al...... 526/56 16 Claims, No Drawings 4,161,571 1. 2 the use of a complex-forming agent such as acetylace PROCESS FOR PRODUCTION OF THE MALEC tone in such a reaction. ANHYDRIDE ADDUCT OF A LIQUID POLYMER As result of an extensive study seeking a gelation inhibitor which exerts a sufficient effect for preventing This application is a divisional, of copending applica the formation of gels in the addition reaction of maleic tion Ser. No. 733,914, filed on Oct. 19, 1976 now U.S. anhydride to give conjugated diene polymers even Pat. No. 4,080,493. when employed in a small amount, it has been found The present invention relates to a process for produc that imidazoles, thiazoles, metal salts of mercapto tion of the maleic anhydride adduct of a liquid polymer thiazoles, urea derivatives, naphthylamines, nitrosa having a maleic anhydride addition amount of 2 to 70% 10 mines, iron and its compounds, and specific halogen by weight. compounds have such an effect and are utilizable as the Hitherto, it is well known to prepare the important gelation inhibitor. materials for paints by reacting natural unsaturated oils The present invention is based on the above finding such as soybean oil, linseed oil or castor oil with maleic and provides a process for production of the maleic anhydride. Many attempts have been made to use sub 5 anhydride adduct of a liquid polymer having a molecu stitutes for the natural unsaturated oils in production of lar weight of 150 to 5,000 and a viscosity of 2 to 50,000 the said materials. For example, Japanese Patent Publi cps at 30° C. in the presence of at least one compound, cation No. 21193/1961 discloses the production of the as a gelation inhibitor, selected from the group consist materials for alkyd resins by reacting cyclododecatriene ing of imidazoles, thiazoles, metal salts of mercapto with maleic anhydride. Japanese Patent Publication No. 20 thiazoles, urea derivatives, naphthylamines, nitrosa 954/1971 discloses the production of a modified poly mines, iron and its compounds and specific hydrogen mer by the addition reaction of maleic anhydride to compounds, said liquid polymer being selected from the give low molecular weight polybutadiene having the group consisting of liquid polybutadienes, liquid poly 1,2-structure in an amount of not less than 80%. Japa isoprenes and liquid copolymers comprising units of nese Patent Publication No. 7269/1971 discloses a 25 butadiene or isoprene and units of at least one com method for the preparation of a water-soluble resin by pound selected from the group consisting of other diole neutralizing the said modified polymer or its esterified fins, olefins and aromatic vinyl compounds. product with ammonia or an amine. Compared with the said gelation inhibitors as dis In the reaction wherein maleic anhydride adds to the closed in Japanese Patent Publication Nos. 26870/1968 polymers resulting from conjugated diolefins, the ad 30 and 44557/1972, the gelation inhibitors used in the pres ducts are generally prepared by heating and, in this ent invention have various advantages. For instance, reaction, there is usually observed a tendency that, the gelation inhibitors of this invention can reduce suffi while the addition reaction proceeds, the double bonds ciently and satisfactorily the viscosity of the reaction of the polymers are crosslinked with other molecules mass by the use of a smaller amount than that of the according to the radical addition, whereby the viscosity 35 known gelation inhibitors. This is advantageous in pro of the reaction mass increases. When the viscosity is duction of resinous materials to be used for paints since further increased, the reaction mass in the reaction ves the influence by the gelation inhibitor can be sup sel completely forms a gel to make the after-treatment pressed. Further, for instance, the coloration of the very troublesome. Even if the gel is not formed, the maleinized product caused by the gelation inhibitors of increase of the viscosity in the maleinization causes the invention is much less than that caused by the various difficulties. For instance, the paints prepared by known gelation inhibitors. This apparently contributes the use of the resulting maleinized products form a to the production of resinous materials of higher qual coating film having inferior physical properties. Fur ity. ther, for instance, the controls of the conversion of The working mechanism of the gelation inhibitors maleic anhydride and of the viscosity of the reaction 45 according to the present invention is still unclear. How mass for obtainment of the maleinized products having ever, it is presently assumed that they are effective in a suitable viscosity for paints are quite difficult. decomposition and elimination of such radicals as hy Various trails have been made to overcome the said droperoxy groups, oxy radicals and polymer radicals difficulties. For example, Japanese Patent Publication present in the molecules of the liquid polymer and/or No. 3547/1973 proposes to use cyclic ethers, aldehydes 50 molecular oxygen existing in the liquid polymer. or ketones as a gelation inhibitor in the maleinization As the liquid polymer, there are utilizable liquid poly reaction. Further, as such gelation inhibitor, there are butadienes, liquid polyisoprenes, liquid butadiene co proposed the uses of amides (Japanese Patent Publica polymers and liquid isoprene copolymers, which may tion No. 3544/1973), catechols (Japanese Patent Publi have a molecular weight of 150 to 5,000 and a viscosity cation (unexamined) NO. 7895/1975), naphthols (Japa 55 of 2 to 50,000 cp at 30 C, irrespective of the proportion nese Patent Publication (unexamined) No. 87491/1975), of the cis-, trans-, vinyl- and 3,4-structures constituting phenothiazines (Japanese Patent Publication (unexam the micro structure of the liquid polymer. In case of the ined) No. 132013/1974), etc. . liquid polymer being a low molecular weight copoly On the other hand, Japanese Patent Publication No. mer of butadiene or isoprene with styrene, it may con 26870/1968 discloses the preparation of maleinized tain styrene units in a proportion of not more than 40% products by heating a liquid polybutadiene having the by weight. The said liquid polymer can be prepared in cis-1,4 structure in an amount of not less than 50% and a conventional procedure, for instance, as disclosed in a viscosity of 30 to 30,000 cp (centipoise), particularly U.S. Pat. No. 3,428,699. 80 to 10,000 cp, at 50 C. with maleic anhydride in the The addition reaction of maleic anhydride to the presence of a copper compound. This method is charac 65 liquid polymer in the presence of the gelation inhibitor terized in that the viscosity in maleinization is reduced may be carried out by charging the liquid polymer, by the existence of the copper compound. Further, maleic anhydride and the gelation inhibitor into a reac Japanese Patent Publication No. 44557/1972 proposes tion vessel in an optional order and then heating at an 4,161,571 3 4. elevated temperature until the maleinization is com halogen atom, a mercapto group, a hydroxyl group or a pleted. Practically, for instance, the liquid polymer and hydroxymethyl group, or a group of the formula: the gelation inhibitor are first charged into a reaction -SNR7R8 in which R7 and R8 are each a hydrogen vessel and kept at a temperature of 10 to 270° C. for a atom, an alkyl group having 1 to 8 carbon atoms or an period of 0 to 20 hours. Then, maleic anhydride is added alicyclic group. Specific examples are 2-methylthiazole, thereto, and the resultant mixture is heated at a tempera 4-methythiazole, 5-methylthiazole, 2,4-dimethyl ture of 120' to 230 C, preferably of 170° to 210°C., for thiazole, 2,5-dimethylthiazole, 4,5-dimethyltiazole, a period of 1 to 10 hours in a nitrogen stream under 2,4,5-trimethylthiazole, 2-ethylthiazole, 2-phenyl stirring. Alternatively, the liquid polymer, maleic anhy thiazole, 4-phenylthiazole, 5-phenylthiazole, 2-methyl dride and the gelation inhibitor may be charged in a 10 4-phenylthiazole, 4-methyl-5-phenylthiazole, 4,5- reaction vessel from the beginning and then heated at a diphenylthiazole, 2-methyl-4,5-diphenylthiazole, 2 temperature of 120' to 230 C., preferably of 160' to methylcyclohexenothiazole, 2-mercaptocyclohexeno 190 C., for a period of 1 to 10 hours in a nitrogen thiazole, 2-chlorothiazole, 2-bromothiazole, 2-chloro-4- stream under stirring. Since the maleinization proceeds methylthiazole, 4-chloromethylthiazole, 4-chlorometh almost quantitatively, the recovery of unreacted materi 15 yl-2-methylthiazole, 4-chloromethyl-2-phenylthiazole, als from the reaction mixture is normally unnecessary. 2-hydroxy-4-methylthiazole, 2-methoxy-4-methyl The content of the added maleic moiety in the malei nized product may be usually from 2 to 70% by weight. thiazole, 2-hydroxy-5-methylthiazole, 2-hydroxy-4,5- When the maleinized product is blended with an inor diphenylthiazole, 2-hydroxymethyl-4-methylthiazole, ganic pigment to prepare a paint composition, the ma 20 2-aminothiazole, 2-amino-4,5-diphenylthiazole, 2 leic anhydride content is particularly desired to be not amino-5-phenylthiazole, benzthiazole, 2-ethylbenz less than 2% by weight. thiazole, 2-methylbenzthiazole, 2-phenylbenzthiazole, As the gelation inhibitor used in the present inven 2-chlorobenzthiazole, 2-hydroxybenzthiazole, 2 tion, there may be exemplified the following com hydroxy-5-methylbenzthiazole, 2-aminobenzthiazole, pounds: 25 2-amino-6-methylbenzthiazole, 2-mercaptobenz (1) Imidazoles of the formulae: thiazole, etc. When X is a group represented by the formula: -SNR7R8, the thiazoles are generally called H H "thiazylsulfenamides,' and their examples include N N N ethylthiazylsulfenamide, N-propylthiazylsulfenamide, R n n 30 N-butylthiazylsulfenamide, N-amylthiazylsulfenamide, C-X and C-X N-octylthiazylsulfenamide, N-cyclohexylthiazylsul 2 2 fenamide, N-oxydiethylenethiazylsulfenamide, N-ethyl R2 1 N benzthiazylsulfenamide, N-propylbenzthiazylsulfena R3 mide, N-butylbenzthiazylsulfenamide, N-octylbenz 35 thiazylsulfenamide, N-cyclohexylbenzthiazylsulfena wherein R, R2 and R3 are each a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a halogen mide, N-oxydiethylenebenzthiazylsulfenamide and the atom and X is a hydrogen atom, an alkyl group having like. Among the foregoing thiazoles, benzthiazoles are 1 to 8 carbon atoms, a phenyl group, a mercapto group particularly preferred. or a halogen atom. Specific examples are imidazole, (3) Metal salts of mercaptothiazoles of the formula: 4-methylimidazole, 2-methylimidazole, 2 phenylimidazole, 4-phenylimidazole, 2,4-dime thylimidazole, 4,5-dimethylimidazole, 2,4- N diphenylimidazole, 4,5-diphenylimidazole, 2,4,5-tri S. phenylimidazole, 2-bromo-4-methylimidazole, 2 bromo-4-phenylimidazole, 4-bromo-1-methylimidazole, 45 (SCBs 1 2 2,4-dibromoimidazole, 2,4,5-tribromoimidazole, 2,4,5- triiodoimidazole, 2-mercapto-imidazole, 2-mercapto-4- methylimidazole, 2-mercapto-4,5-dimethylimidazole, wherein R9, R10 and R11 are each a hydrogen atom, an 2-mercapto-4-phenylimidazole, benzimidazole, 2 alkyl group having 1 to 8 carbon atoms, a halogen atom methylbenzimidazole, 2-ethylbenzimidazole, 2-vinyl 50 or a phenyl group and M is zinc, aluminum, magnesium benzimidazole, 2-phenylbenzimidazole, 2-benzylben or calcium. Specific examples include zinc salts, cal zimidazole, 5-methylbenzimidazole, 2-mercaptoben cium salts, magnesium salts and aluminum salts of 2 zimidazole, 2-mercapto-5-methylbenzimidazole, etc. mercaptothiazole, 2-mercapto-4-methylthiazole, 2-mer Among these imidazoles, mercapto-imidazoles and capto-5-methylthiazole, 2-mercapto-4,5-dimethyl 55 thiazole, 2-mercapto-4-ethylthiazole, 2-mercapto-4- benzimidazoles are preferred. chlorothiazole, 2-mercapto-4-phenylthiazole, 2-mercap (2) Thiazoles of the formulae: to-4-methyl-5-phenylthiazole, 2-mercaptocyclohexeno thiazole, 2-mercaptobenzthiazole and the like. Among Rs these salts, metal salts of benzthiazoles are particularly R4 s preferred. -X and (4) Urea derivatives of the formula: 1 R5 S R12-NH wherein R4, R5 and R6 are each a hydrogen atom, an 65 alkyl group having 1 to 8 carbon atoms, a halogen atom or a phenyl group and X" is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a phenyl group, a

4,161,571 5 6 wherein R12 and R13 are each a hydrogen atom, an alkyl (B) Hydrogen halogenides represented by the for group having 1 to 8 carbon atoms or a phenyl group and mula: HX' wherein X' is a chloride, bromine or iodine X" is an imino group or a sulfur atom. Specific examples atom are used. Specific examples include hydrogen include guanidine, diphenylguanidine, dimethylguani chloride, hydrogen bromide and hydrogen iodide. dine, diphenylthiourea and the like. The inorganic or (C) Alkyl metal halides represented by the formula: organic salts (e.g., hydrochlorides, sulfates, carbonates, acetates, oxalates) of the foregoing compounds as well RMY-n as the adducts of the foregoing compounds with acetic anhydride, phthalic anhydride, maleic anhydride, etc., wherein M' is a metal belonging to Group (III) or (IV) are also utilizable. O of the Periodic Table, R is an alkyl group, Y is a chlo (5) Naphthylamines rine atom, a bromine atom or an iodine atom, m is a As the naphthylamines, a-naphthylamine, g-naph valence of the metal (M) and n is a positive integer thylamine, N-phenyl-a-naphthylamine, N-phenyl-g- smaller than m are used. Specific examples include naphthylamine and N,N'-di-3-naphthyl-p- dimethylaluminum chloride, diethylaluminum chloride, phenylenediamine are preferred. 15 disobutylaluminum chloride, ethylaluminum sesqui (6) Nitrosamines of the formula: chloride, ethylaluminum dichloride, diethylaluminum bromide, diethylaluminum iodide, dimethylboron monochloride, diethylboron monochloride, dibutylbo ron monochloride, methylboron dichloride, ethylboron 20 dichloride, butylboron dichloride, boron trichloride, dimethylboron monobromide, diethylboron monobro mide, dibutylboron monobromide, diphenylboron wherein R14 and R15 are each an alkyl group having 1 to monobromide, methylboron dibromide, ethylboron 8 carbon atoms or a phenyl group. Preferred com dibromide, propylboron dibromide, butylboron dibro pounds are dimethylnitrosamine, diethylnitrosamine, 25 mide, boron tribromide, dimethylboron monoiodide, dipropylnitrosamine, dibutylnitrosamine, dioctylni diethylboron monoiodide, dipropylboron monoiodide, trosamine, didodecylnitrosamine, diphenylnitrosamine, dibutylboron monoiodide, diphenylboron monoiodide, ditolylnitrosamine, dicyclohexylnitrosamine, etc. methylboron diiodide, ethylboron diiodide, butylboron (7) Iron and its compounds diiodide, borontriiodide, methyltin trichloride, dimeth Among iron and its compounds, preferred are those 30 yltin dichloride, ethyltin trichloride, butyltin trichlo soluble in organic solvents. However, even the insolu ride, diphenyltin dichloride, trimethyltin bromide and ble compounds have an antigelling effect. As the or trimethyltin iodide. ganic salts of iron, there may be exemplified the iron (D) Halogenated compounds of aliphatic or alicyclic salts of organic carboxylic acids such as iron acetate, 35 hydrocarbons having 1 to 8 carbon atoms are used. iron naphthenate, iron octylate and iron benzoate. As Specific examples include carbon tetrachloride, chloro the organic complexes of iron, there may be exemplified form, bromoform, iodoform, dichloroethane, bromo the complex between iron chloride and pyridine, tris chloromethane, dibromoethane, diiodomethane, ethyl (dipyridyl)iron chloride, bis-(ethylenediamine)iron sul bromide, ethyl chloride, isobutyl chloride, isobutyl bro fate and the like. The chelate compounds of iron such as mide, n-butyl bromide, tert-butyl bromide, tert-butyl bis-(acetylacetonate)iron, bis-(ethylacetoacetate)iron chloride, 2-iodopropane, 2-bromodecane, 1,1,1-tri and bis-(dimethylglyoximate)iron may be also em chloroethane, 1,1,2-trichloroethane, pentachloroethane, ployed. Further, inorganic iron compounds such as iron hexachloroethane, hexachlorocyclopentadiene, 5-chlo sulfate, iron nitrate, iron oxide, ferrous chloride, ferric ronorbornane, 5-chloromethylnorbornane, 5-bromon chloride, ferrous bromide, ferric bromide, iron iodide 45 orbornane, 5-bromomethylnorbornane, etc. and iron powder are utilizable. (E) Compounds of the formula: (8) Halogen-containing compounds (A) Elements belonging to Group (III), (IV), (V) or R9 (VI) in the Periodic Table are used in the form of chlo rides, bromides or iodides, or ether complexes, ester 50 is complexes or aldehyde complexes thereof. As the ele g-ri, ments, there may be exemplified phosphorus, boron, R18 aluminum, gallium, indium, thallium, titanium, germa R20 nium, zirconium, tin, vanadium, arsenic, antimony, tan talum, bismuth, chromium, molybdenum and the like. 55 wherein R16 is a chlorine atom, a bromine atom or an Specific examples include boron trichloride, aluminum iodine atom, R17 and R18 are each a hydrogen atom, a trichloride, gallium trichloride, indium trichloride, tita chlorine atom, a bromine atom, an iodine atom, a lower nium tetrachloride, zirconium tetrachloride, tin chlo alkyl or a phenyl group and R19 and R20 are each a ride, antimony trichloride, antimony pentachloride, hydrogen atom a halogen atom, an alkyl group having phosphorus trichloride, tungsten hexachloride, molyb 1 to 4 carbon atoms or a halogen substituted alkyl group denum tetrachloride, phosphorus pentachloride, phos are used. Specific examples include benzyl chloride, phorus tribromide, phosphorus pentabromide, arsenic benzyl bromide, benzyl iodide, a-methylbenzyl bro trichloride, arsenic tribromide, antimony tribromide, mide, a-methylbenzyl chloride, triphenylmethyl chlo antimony triiodide, antimony pentabromide, boron tri ride, triphenylmethyl bromide, benzotrichloride, 2,4- bromide, boron triiodide, aluminum tribromide, tita 65 dichlorobenzotrichloride, benzotribromide, a,2,4-tri nium tetrabromide, titanium tetraiodide and the like, chlorotoluene, o,3,4-trichlorotoluene, m-xylylene chlo and ether complexes, ester complexes and aldehyde ride, m-xylylene bromide, o-xylylene bromide, p-xyly complexes of the foregoing compounds. lene bromide, o-xylylene chloride, p-xylylene chloride, 4,161,571 7 8 m-xylylene tetrabromide, o-xylylene tetrabromide, p charged, and a designed amount of the gelation inhibi xylylene tetrabromide, a,a,a,a',a",a'-hexachloro-m- tor as shown in Table 1 was added thereto: xylene, a,a,a,a',a", a'-hexachloro-o-xylene, benzal chloride, 2,6-dichlorobenzal chloride and the like. Viscosity (cp, 20° C) 660 (F) As the alkynyl halides, there may be exemplified Specific gravity (d.420, g/ml) 0.904 propargyl chloride, propargyl bromide, etc. Iodine value (iodine g/100g) 450 (G) Ketones containing a chlorine atom or a bromine Molecular weight (measured by 1,730 atom are used. Specific examples include 1,3-dichlor a pressure osmometer) oacetone, 1,1,3,3-tetrachloroacetone, bronoacetone, Structure (%) ( trans-1,4cis-14 structure structure 2375 1,3-dibromoacetone, hexachloroacetone and the like. 10 vinyl structure 2 (H) Halogen-containing allyl compounds of the for mula: After replacing the air in the flask by nitrogen gas, the mixture was heated at 150° C. for 1 hour with stir 15 ring. Then, 34 g of maleic anhydride were added wherein R21 is a hydrogen atom or an aliphatic hydro thereto, and the maleinization reaction was carried out carbon group having 1 to 6 carbon atoms and Y is a at 190° C. for 5 hours, during which the reaction mix chlorine atom, a bromine atom or an iodine atom are ture was sampled at 3, 4 and 5 hours from the initiation used. of the reaction and subjected to quantitative measure Among the gelation inhibitors described above, thia 20 ments of the conversion of maleic anhydride by means zoles, metal salts of mercaptothiazoles, naphthylamines, of gas chromatography. After completion of the reac and iron and its compounds are especially preferred. tion, the produced maleinized polybutadiene was dis The gelation inhibitor may be used in an amount of solved in xylene to make a solid content of 70% and 0.001 to 5%, preferably 0.005 to 0.5%, based on the measured for viscosity at 25 C. by means of the E-type liquid polymer. The gelation inhibitor may be employed 25 viscometer (manufactured by Tokyo Keiki Co., Ltd.). as such or in the form of a solution in an organic solvent. The results are shown in Table 1 wherein the results The addition reaction of maleic anhydride to the from the maleinization reactions carried out with cop liquid polymer is usually carried out without any sol per naphthenate as the gelation inhibitor or without any vents. However, organic solvents may be used, if neces gelation inhibitor are also indicated for comparison. sary. Examples of such solvents are aliphatic hydrocar 30 From Table 1, it is apparent that the gelation inhibi bons (e.g., liquid paraffin, n-paraffin, petroleum benzin), tors according to the present invention have a higher alicyclic hydrocarbons (e.g., cyclohexane, isopropylcy effect than copper naphthenate at the same amount clohexane), aromatic hydrocarbons (e.g., benzene, tolu used. It is also apparent that the gelation inhibitors ac ene, xylene, durene), ester compounds (e.g., ethyl ace cording to the present invention do not cause any mate tate, butyl acetate), etc. Other organic solvents such as rial reduction of the conversion of maleic anhydride. Table 1 Viscosity Gelation inhibitor in solu- Conversion of Maleic Amount used tion anhydride (% Run No. Name (% by weight) (cp, 25 C. 3 hrs. 4 hrs. 5 hrs. 1 2-Mercaptobenzthiazole 0.0300 820 98.8 99.1 99.9 2 2-Mercaptobenzimidazole 0.0300 960 98.7 99.2 99.9 3 Diphenylguanidine 0.0300 1050 98.9 99. 99.9 4 2-Mercaptoimidazole 0.0300 930 98.9 99.1 99.9 5 2-Hydroxy-4-methylthiazole 0.0300 1530 98.6 99.2 99.9 6 Diphenylthiourea 0.0300 1320 98.7 99.1 99.9 Reference None - 4004 98.8 99.1 99.9 No. 1 Reference Copper naphthenate 0.0300 2960 98.7 99. 99.9 No. 2

acetone, methyl ethyl ketone and dioxane are also utiliz able. The maleic anhydride adducts obtained by the pres EXAMPLE 2 ent invention can remarkably be accelerated in the air 55 Into a 300 ml volume flask, 166 g of the liquid polybu drying rate by adding a conventional hardening agent tadiene as in Example 1 were charged, and a designed such as cobalt naphthenate thereto. Further, polyols, amount of the gelation inhibitor as shown in Table 2 polymercaptanes, polyamines, polyphenols and the like was added thereto. After replacing the air in the flask can be used for hardening the coating film. by nitrogen gas, the mixture was heated at 100° C. for 1 Practical embodiments of the present invention are 60 hour. Then, 34 g of maleic anhydride were added illustratively shown in the following examples, which thereto, and the maleinization reaction was carried out are not however intended to limit the present invention at 190° C. for 5 hours. After completion of the reaction, thereto. In these examples, 9% are usually by weight the produced maleinized polybutadiene was dissolved unless otherwise indicated. in xylene to make a solid content of 75% and measured 65 for viscosity at 25 C. EXAMPLE 1. The results are shown in Table 2, from which it is Into a 300 ml volume flask, 160 g of a liquid polybuta apparent that the gelation inhibitors according to the diene having the following physical properties were present invention have an excellent effect.

4,161,571 9 10 Table 2 Gelation Inhibitor Viscosity Amount used in solu- Conversion of (ppm, based tion maleic anhy Run No. Name on polymer) .. (cp, 25 C.) ride (%) 1 N-t-Butylbenzthiazylsulfenamide 100 -750 99.9 2 N-Cyclohexylbenzthiazylsulfen- 100 830 99.9 amide 3 N-Hydroxydiethylenebenzthiazyl- 200 660 99.9 sulfenamide 4. Zinc salt of 2-mercaptobenz- 100 600 99.9 thiazole 5 Guanidine hydrochloride 100 430 99.9 6 Diphenylguanidine hydrochloride 100 480 99.9 7 N-Nitrosodiphenylamide 100 630 99.9 Reference None m 6800 99.9 No. 1 Reference Copper naphthenate 300 2600 99.9 No. 2 -- resulting maleinized product was determined on the EXAMPLE 3 20 xylene solution3. havingp a solid content of 75%. The gelation inhibitors according to the present in The results are shown in Table 3, from which it is vention were tested for the antigelling effect on the apparent that the gelation inhibitors according to the addition reaction of maleic anhydride to a mixture of a present invention have a high effect. Table 3 Gelation inhibitor Viscosity Amount used in solu- Conversion of (ppm, based tion maleic anhyd Run No. Name on polymer) (cp, 25 C.) ride (%) 1 N-Phenyl-a-naphthylamine 200 930 99.9 2 Diphenylguanidine hydrochloride 200 850 99.9 3. Zinc salt of 2-mercaptobenz- 100 2300 99.9 thiazole 4. Guanidine carbonate 100 2080 99.9 5 N-Nitrosodiphenylamine 100 1900 99.9 6 N-Cyclohexylbenzthiazylsulfen- 100 280 99.9 amide Reference None - reaction No. 1 mass gelled after 2 hrs. at 190 C. reaction stopped liquid polybutadiene having a high content of the cis-1,4 EXAMPLE 4 structure and a liquid polybutadiene having a high con tent of the 1,2-structure. Said cis-1,4-type liquid polybu 45 Maleinization reaction was carried out under the tadiene used was the same one as in Example 1, and said same conditions as in Example 1 except that a different 1,2-type liquid polybutadiene used was the one having a gelation inhibitor was used. The resulting maleinized number average molecular weight of 1,000 and consist polybutadiene was dissolved in xylene to make a solid ing of 92% of the 1,2-structure and 8% of the trans-1,4 content of 70% and subjected to measurement for vis structure (trade name "B-1000" manufactured by Nip cosity at 25 C. by means of the E-type viscometer. pon Soda Co., Ltd.). The results are shown in Table 4 wherein the results To a 300 ml volume flask equipped with a stirrer were from the maleinization reactions carried out with ace added 83 g of the cis-1,4 type polybutadiene and 83 g of tylacetone, copper naphthenate, hydroquinone or 2,6- the 1,2-type polybutadiene. After replacing the air in di-tert-butoxytoluene as the gelation inhibitor or with the flask by nitrogen gas, the mixture was heated. When 55 out any gelation inhibitor are also indicated for compar the temperature reached 100' C., 28 g of maleic anhy SO. dride and the gelation inhibitor were added thereto, From Table 4, it is apparent that both hydroquinone followed by reaction at 190° C. for 5 hours. The conver and 2,6-di-tert-butoxytoluene exhibit little or no gela sion of maleic anhydride was quantitatively measured tion inhibiting effect, while the gelation inhibitors ac by means of gas chromatography. The viscosity of the cording to the present invention can keep the viscosity fairly low. Table 4 Gelation inhibitor Amount used Viscosity in solution Conversion of maleic " . . (% by (cp, 25 C.) anhydride (%) Run No. Name weight) 3 hrs. 4 hrs. 5 hrs. 3 hrs. . 4 hrs. 5 hrs, Hexachloroacetone 0.021 4639 6656 7475 99.2 99.9 99.9 4,161,571 11. 12 Table 4-continued Gelation inhibitor Amount used Viscosity in solution Conversion of maleic (% by - (cp. 25 C.) - anhydride (%) - Run No. Name weight) 3 hrs. 4 hrs. 5 hrs. 3 hrs. 4 hrs. 5 hrs. 2 Benzotrichloride 0.037 1265 1715 2355 98.9 99.4 99.9 3 Phosphorus tri- 0.021 904 1214 1344 97.5 99.8 99.9 chloride 4 Aluminum tri- 0.025 563 1170 1221 98.8 99.3 99.9 chloride 5 Titanium tetra- 0.027 963 1114 1142 98.9 99.3 99.9 chloride Reference None - increase gela- m - m - No. 1 in visco- tion sity Reference Hydroquinone 0.415 15300 23000 gela- 98.9 99.5 99.9 No. 2 tion Reference 2,6-Di-tert-butoxy- 0.500 increase - r -- m - No. 3 toluene in visco sity Reference Copper naphthenate 0.02 4350 6700 8630 98.6 99.1 99.9 No. 4 Reference Acetylacetone 0,100 21320 28750 362.00 98.8 99.6 99.9 No. 5 EXAMPLE 5 polybutadiene used had the following physical proper ties: To a 200 ml volume three-necked glass flask were charged the gelation inhibitor and 100 g of a liquid Viscosity (cp, 20' C) 800 polybutadiene having the following physical properties: 30 Specific gravity (da, g/ml) 0.898 Iodine value (iodine g/100 g) 450 Molecular weight (measured by a 1,970 pressure osmometer) Viscosity (cp, 30 C.) 74 Micro-structure (%) cis-1,4 structure 79 Molecular weight (measured by 660 ( trans-14 structure 19 a pressure osmometer) 35 vinyl structure 2 Specific gravity (d.420, g/ml) 0.872 Iodine value (Wijs method) 461 Micro-structure (%) cis-1,4 structure 65.1 During the maleinization reaction, samplings were ( trans-1,4 structure 27.0 carried out at 3, 4 and 5 hours from the initiation of the vinyl structure 7.9 reaction, and the quantitative measurements of the con version of maleic anhydride were carried out by means After replacing the air in the flask by nitrogen gas, of gas chromatography. After completion of the reac the mixture was stirred vogorously at 150 C. for 1 tion, the resulting maleinized polybutadiene was dis hour. Thereafter, a designed amount of maleic anhy solved in xylene to make a solid content of 60% and dride was added thereto, and maleinization was carried measured for viscosity at 25 C. by means of the E-type out at 190° C. for 5 hours in a nitrogen stream. After 45 viscometer. completion of the reaction, the reaction product was The results are shown in Table 6 wherein the results sampled and tested for solubility in toluene. from the maleinization reactions carried out with cop The results are shown in Table 5 wherein the results per naphthenate as the gelation inhibitor or without any from the maleinization reaction carried out without any gelation inhibitor are also indicated for comparison. gelation inhibitor are also indicated for comparison. 50 When the gelation inhibitor was not used, the reaction Table 5 Maleic anhydride Gelation inhibitor conversion Weight % in Weight % in of maleic Amount the reac- Amount eac- Viscosity anhydride Solubility Run No. (g) tion mass Kind (g) tion mass (cp, 25 C.) (%) in toluene 20.5 17 Iron 0.48 0.40 860 99 Completely naph- dissolved thenate Reference 20.5 17 None m - 2450 99 Completely No. 1 dissolved mass gelled 3 hours after the initiation of the reaction and adhered to the stirrer. After the gel was once 65 formed, it was no longer soluble in xylene. EXAMPLE 6 Fromp Table 6, it is 3.apparent that they gelation inhibi Maleinization reaction was carried out under the tors according to the present invention have a higher same conditions as in Example 1 except that the liquid viscosity reducing effect than copper naphthenate.

4,161,571 13 14 Table 6 Gelation inhibitor Weight % Weight of in the metal Viscosity in solu- Conversion of maleic maleinized atom - tion (cp. 25" C.) ahydride (% Run No. Kind product (ppm) 3 hrs, 4 hrs. 5 hrs. 3 hrs, 4 hrs. 5 hrs. 1 Iron naph- 0,363 306 614 888 050 97.3 99.0 99.9 thenate 2 Iron naph- 0.073 61 n-mow- m 96.7 99.2 99.9 thenate 3 Ferric 0.0253 35 367, 48 481 98.1 99.9 99.9 chloride Reference None w gela- m No. 1 tion Reference Copper 0.421 306 804 1229 423 97.6 99.3 99.9 No. 2 naphthe rate Reference Hydroqui- 0.421 w- gela- www. www- www. m No. 3 de tion Note: The weight of the metal atom is indicated by the amount of the metal compound in the liquid polybutadiene in terms of the metal atom (ppm). The ferric chloride means anhydrous ferric chloride, and it was dissolved in methylethylketone to make a concentration of 0.05 gam and used for the reaction.

EXAMPLE 7 solid content of 75%, and the resultant xylene solution Thirty grams of a liquid polyisoprene having the was measured for viscosity at 25 C. by means of the following physical properties, 7.5g of maleic anhydride 25 E-type viscometer. and a designed amount of the gelation inhibitor were The results are shown in Table 8. charged in a flask: Table 8 Visco- Conver 450 sity sion MEc 110 30 Gelation Inhibitor in of Iodine value 400 Amount solu- maleic Micro-structure (%) cis-1,4-structure 34 used on tion anhy trans-14 structure 41 the poly- (cp, dride 3,4-structure 24.0 Run No. Name mer) 25° C) (%) 12-structure 1.0 35 1 N-Phenyl-a- 200 1080 99.9 naphthyl After replacing the airby nitrogen gas, the sixture Reference miI an 1800 99.9 was heated at 190° C. for 5 hours with stirring. Thereaf- No. 1 ter, the resulting maleinized polyisoprene was diluted with xylene to make a solid content of 75%, and the What is claimed is: resulting solution was measured for viscosity at 25 C. 1. A process for the production of the maleic anhy by means of the E-type viscometer. dride adducts of a liquid polymer having a maleic anhy The results are shown in Table 7. dride addition amount of 2 to 70% by weight, which Table 7 comprises reacting a liquid polymer having a molecular Visco- conver 45 weight of 150 to 5,000 and a viscosity of 2 to 50,000 sity sion centipoise at 30 C, said liquid polymer being selected Gelation Inhibitor of from the group consisting of liquid polybutadienes, A. solu- t liquid polyisoprenes and liquid copolymers comprising th psy. E. E. units of butadiene or isoprene and units of at least one Run No. Name mer) 25° C) (a) 50 compound selected from the group consisting of other 1 N-Phenyl-a- 200 480 99.9 diolefins, olefins and aromatic vinyl compounds, with naphthyl- maleic anhydride in the presence of at least one com amine pound, as a gelatin inhibitor, selected from the group Reference None WW 940 99.9 consisting of No. 1 55 (a) organic salts of iron, organic complexes of iron, chelate compounds of iron and inorganic com EXAMPLE 8 pounds off iron;iron: (b) chlorides, bromides and iodides of the elements Fifteen grams of the liquid polyisoprene as in Exam belonging to Groups (III), (IV), (V) or (VI) of the ple 7, 15 g of a liquid polybutadiene having a high con- 60 Periodic Table, and ether complexes, ester com tent of the 1,2-structure (i.e., the one having a number plexes and aldehyde complexes thereof; and average molecular weight of 1,000 and consisting of (c) alkyl metal halides of the formula: 92% of the 1,2-structure and 8% of the trans-1,4 struc ture), 7.5g of maleic anhydride and a designed amount of the gelation inhibitor were charged in a flask. After 65 replacing the air by nitrogen gas, the mixture was wherein M' is a metal belonging to Group (III) or (IV) heated at 190° C. for 5 hours with stirring. The resulting of the Periodic Table, R is alkyl having 1 to 8 carbon maleinized product was diluted with Xylene to make a atoms, Y is chlorine, bromine or iodine, m is an atomic 4,161,571 15 16 the Periodic Table, or an ether complex, ester complex valence of the metal M", and n is a positive integer or aldehyde complex thereof. smaller than m. 10. A method according to claim 9, wherein the ele 2. A method according to claim 1, wherein the gela ment is phosphorus, boron, aluminum or titanium. tion inhibitor is an organic salt of iron. 11. A method according to claim 9, wherein the com 3. A method according to claim 2, wherein the or plex is the ether complex, ester complex or aldehyde ganic acid salt of iron is a carboxylic acid salt of iron. complex of boron trichloride, aluminum trichloride, 4. A method according to claim 1, wherein the gela titanium tetrachloride, phosphorus trichloride, phos tion inhibitor is an organic complex or chelate of iron. phorus pentachloride, phosphorus tribromide, phospho 10 rus pentabromide, boron tribromide, boron triiodide, 5. A method according to claim 4, wherein the or aluminum tribromide, titanium tetrabromide or titanium ganic complex or chelate of iron is tris-(dipyridyl)iron tetraiodide. chloride, bis-(ethylenediamine)iron sulfate, bis 12. A method according to claim 1, wherein the gela (acetylacetonate)iron, bis-(ethylacetoacetate)iron, bis tion inhibitor is said alkyl metal halide of the formula: (dimethylglyoximate)iron or the complex between iron 15 chloride and pyridine. 6. A method according to claim 2, wherein the or in which M' is aluminum, boron or tin. ganic salt of iron is iron acetate, iron naphthenate, iron 13. A method according to claim 1, wherein the octylate or iron benzoate. 20 amount of gelation inhibitor is 0.001 to 5% by weight 7. A method according to claim 1, wherein the gela based on the liquid polymer. 14. A method according to claim 13, wherein the tion inhibitor is an inorganic acid salt of iron. amount of gelation inhibitor is 0.005 to 0.5% by weight 8. A method according to claim 7, wherein the inor based on the liquid polymer. ganic acid salt of iron is iron sulfate, iron nitrate, ferrous 25 15. A method according to claim 1, wherein the addi chloride, ferric chloride, ferrous bromide, ferric bro tion reaction is carried out at 120' to 230 C. for 1 to 10 mide or iron iodide. hours. 9. A method according to claim 1, wherein the gela 16. A method according to claim 15, wherein the tion inhibitor is the chloride, bromide or iodide of an reaction temperature is 160 to 190° C. element belonging to Group (III), (IV), (V) or (VI) of 30 k k

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. : 4,161,571. DATED : July 17, 1979 NVENTOR(S) : Seimei YASUI et all

it is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

IN THE HEADING: Under 30 Foreign Application Priority Data, add the

following:

--Oct. 22, 1975 (JP) Japan ...... 50 - 127800

Nov. 8, 1975 (JP) Japan ...... 50-154315

Feb. 16, 1976 JP Japan . . . . . e o O e o O O 0 e o 0 a 51-16269 Aug. 4, 1976 JP Japan ...... 51 - 93.454 - - signed and scaled this Twentieth Day of November 1979 SEAL

Attest:

LUTRELLE F. PARKER

RUTH C. MASON Attesting Officer Mcting Commissioner of Patents and Trademarks