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(12) Patent Application Publication (10) Pub. No.: US 2006/0041057 A1 K0echer Et Al

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(12) Patent Application Publication (10) Pub. No.: US 2006/0041057 A1 K0echer Et Al US 20060041057A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2006/0041057 A1 K0echer et al. (43) Pub. Date: Feb. 23, 2006 (54) POLYDIACETYLENE POLYMER BLENDS (22) Filed: Aug. 19, 2004 (75) Inventors: Steven D. Koecher, New Brighton, MN Publication Classification (US); Richard G. Hansen, Mahtomedi, MN (US); Jeffrey J. Cernohous, (51) Int. Cl. Hudson, WI (US) C08F 290/14 (2006.01) (52) U.S. Cl. ................................................................ 525/50 Correspondence Address: 3M INNOVATIVE PROPERTIES COMPANY (57) ABSTRACT PO BOX 33427 Polymer blend compositions that include diacetylene Seg ST. PAUL, MN 55133-3427 (US) ments are provided. The polymers containing diacetylene 9 Segments are capable of a calorimetric indication in response (73) Assignee: 3M Innovative Properties Company to Stimuli, Such as heat, an analyte or exposure to certain environmental factors, despite being blended with other (21) Appl. No.: 10/922,091 materials, Such as polymers or additives. US 2006/004 1057 A1 Feb. 23, 2006 POLYDACETYLENE POLYMER BLENDS 0005. In one embodiment, the reactive emulsifying seg ment is formed from a reactive emulsifying compound BACKGROUND represented by the formula V: 0001 Polymer compositions that include polydiacetylene Segments are used for a variety of applications. Diacetylenes (V) are typically colorless and undergo addition polymerization, G-X-N-Y-G either thermally or by actinic radiation. AS the polymeriza tion proceeds, these compounds undergo a contrasting color change to blue or purple. When exposed to external Stimuli Such as heat, physical StreSS or a change of Solvents or counterions, polydiacetylenes exhibit a further color 0006 wherein G is selected from the group consisting changes produced by distortion of the planar backbone of OH, NHR and SH; each of X and Y may be the same conformation. Polydiacetylene assemblies are known to or different; each of X and Y are independently selected change color from blue to red with an increase in tempera from aliphatic organic radicals having from about 1 to ture or changes in pH due to conformational changes in the about 20 carbon atoms, free of reactive functional conjugated backbone as described in Mino, et al., Langmuir, groups, and combinations thereof; and wherein R can Vol. 8, p. 594, 1992; Chance, et al., Journal of Chemistry be hydrogen or an aliphatic organic radical having from and Physics, Vol. 71,206, 1979; Shibutag, Thin Solid Films, about 1 to about 20 carbon atoms, free of reactive Vol. 179, p. 433, 1989; Kaneko, et al., Thin Solid Films, Vol. functional groupS. 210, 548, 1992; and U.S. Pat. No. 5,672,465. Utilization of this class of compounds is known for use as biochromic 0007. In another embodiment, the reactive emulsifying indicators as discussed in U.S. Pat. No. 5,622,872 and Segment is formed from a reactive emulsifying compound publication WO 02/00920. represented by the formula IV: 0002. In addition to the polymerization of monomeric diacetylenes, it has been demonstrated that the diacetylene (IV) functionality can be incorporated in the repeat Structure of a R polymer backbone. These types of polymers undergo Solid State cross-polymerization on exposure to U.V. radiation a-x--y-g forming polydiacetylene chains. These materials have been referred to as macromonomers due to the Systematic poly merization of the diacetylene units within the backbone Structure of the initial polymer. Examples of polymers 0008 wherein G is selected from the group consisting containing the reactive diacetylene functionality in the of OH, NHR and SH; wherein Q is a negatively charged repeat Structure of the polymer backbone formed by linking moiety selected from COO and SO, or a group that the appropriate difunctional monomers together, wherein is capable of forming Such a negatively charge moiety one of which contains the diacetylene group include the upon ionization; each of X, Y and R' may be the same diacetylene-urethane copolymers described in U.S. Pat. Nos. or different; X, Y, R, and R' are independently selected 4,215,208 and 4,242,440; segmented copolymers formed from aliphatic organic radicals free of reactive func from diisocyanate reacted with elastomeric prepolymer and tional groups, preferably having from about 1 to about chain extended with a diacetylene described in U.S. Pat. No. 20 carbon atoms, and combinations thereof; R can be 4,721,769; linear block copolymers with a soft segment hydrogen; and R is optional if Q is COO and SO. (polyether, polyester, polydiene, polydimethylsiloxane) and a diacetylene-containing hard Segment (Polyurethane, 0009. As used herein, “a,”“an,”“the,”“at least one,” and polyamide, polyester, polyurea) as described in U.S. Pat. No. “one or more' are used interchangeably. Also herein, the 4,767,826; and polyamide-diacetylene copolymers as recitations of numerical ranges by endpoints include all described in U.S. Pat. Nos. 4,849,500 and 4,916,211. numbers Subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.). SUMMARY 0010. The above summary of the present invention is not 0003. The present invention is directed to polymer blend intended to describe each disclosed embodiment or every compositions, and methods of making and using them, that implementation of the present invention. The description include a chromogenic copolymer comprising at least two that follows more particularly exemplifies illustrative diacetylene Segments, and an additive with at least one embodiments. functional characteristic, wherein the polymer blend exhibits chromogenic characteristics of the diacetylene-containing DETAILED DESCRIPTION OF ILLUSTRATIVE copolymer and the functional characteristics of the additive. EMBODIMENTS OF THE INVENTION The additives include, but are not limited to, plasticizers, 0011. The present invention provides polymer blend tackifiers, and/or polymer additives Such elastomers. compositions that include diacetylene Segments. In particu 0004. A chromogenic copolymer is also provided com lar, the present invention is directed to polymers containing prising at least two diacetylene Segments, a linkage Segment; diacetylene Segments that provide a polymer network and at least one reactive emulsifying Segment. A polymer capable of a calorimetric indication in response to Stimuli, blend comprising the chromogenic copolymer with at least Such as heat, an analyte or exposure to certain environmental one reactive emulsifying Segment and an additive with at factors, despite being blended with other materials, Such as least one functional characteristic is also provided. polymers or additives. US 2006/004 1057 A1 Feb. 23, 2006 0012. The diacetylene segments self assemble to form 0016. The ability of polydiacetylene-containing poly ordered assemblies that can be polymerized using any mers to undergo a visible color change upon exposure to a actinic radiation Such as, for example, electromagnetic variety of elements, including ultraViolet light, physical radiation in the UV or visible range of the electromagnetic StreSS, a change in Solvent and a change in counter ion, for Spectrum. The ability of the diacetylene Segments to Self example, make them ideal candidates for the preparation of assemble into ordered assemblies allows the polymerization various Sensing devices. Such Sensing devices can employ to proceed topochemically. The Self-assembly of diacety the diacetylene-containing polymers in Solution or in their lenes depends in large part on two factors: the molecular Solid State. architecture of the diacetylene Starting materials, and the 0017. The structural requirements of diacetylenic poly nature of the copolymer Segment. The diacetylene Starting mer for a given Sensing application are typically application materials of this invention are designed to have a molecular Specific. Features Such as overall chain length, Solubility, architecture which not only enhances but directs their ability polarity, crystallinity, and the presence of functional groups to Self-assemble, by providing an “engineered’ intermolecu for further molecular modification all cooperatively deter lar affinity for the diacetylene molecules to aggregate into mine a diacetylene containing polymer’s ability to Serve as ordered assemblies. An example of a copolymer Segment for the diacetylene materials is a polyurethane polymer System a useful Sensing material. that contributes to the self-assembly of the diacetylenes by 0018. The diacetylene compounds can be easily and providing a hydrogen bonding template for the formation of efficiently polymerized into polydiacetylene-containing polymers that develop a color, Such as blue or purple, as the ordered assemblies of diacetylenes. polymerization proceeds. The polydiacetylene-containing 0013. It is believed that the diacetylene-containing poly polymers can further undergo desired color changes in mers exhibit a color development based on the propensity of response to an external Stimulus Such as heat, a change in the copolymer to Self-assemble at the molecular level into Solvent or counterion, if available, or physical StreSS. ordered morphologies. Consequently, the diacetylene moi 0019. Both the color development of the polydiacetylene eties contained within the polymer backbone are aligned to containing polymer and the Secondary color response of the Such a degree that cross-linking can occur acroSS the polydiacetylene-containing polymers to Stimuli is a function diacetylene functionality, resulting in a conjugated network. in part of
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