Patent ID: 7361696

Claim:
A process for producing a 1,4-di-substituted diacetylene polymer comprising the step of irradiating a solution consisting essentially of dissolved 1,4-di-substituted diacetylene polymer in a polar solvent with a concentration of 10 to 500 mg of 1,4-disubstituted diacetylene polymer/100 ml of polar solvent, with laser light having a wavelength within the range of 250 to 1200 nm, to cause a photodegradation reaction of said polymer, wherein the irradiation time is from 10 seconds to 180 minutes; and wherein said 1,4-disubstituted diacetylene polymer produced by the process is soluble in an organic solvent and is composed of repeating units represented by the general formula ═CR—C≡C—CR′═, (wherein R and R′ represent identical or different monovalent organic substituents,) and has an average degree of polymerization of 4 to 200 and a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight corresponding to said average degree of polymerization (Mn) of 1.1 to 5.0, wherein the organic substituents R and R′ are selected from any of the following: (CH 2 ) m OCONHCH 2 COOC n H 2n+1 (wherein m represents an integer within the range of 3 to 6, and n represents an integer within the range of 1 to 10), (CH 2 ) m CONHCH 2 COOC n H 2n+1 (where in m represents an integer within the range of 3 to 6, and n represents an integer within the range of 1 to 10), (CH 2 ) m OSO 2 C 6 H 4 CH 3 (wherein m represents an integer within the range of 3 to 6) and (CH 2 ) m OCONHCH 2 CONHC n H 2n+1 (wherein m represents an integer within the range of 3 to 6, and n represents an integer within the range of 1 to 10).