Photocrosslinkable polymers based on 4-[5-(4-hydroxyphenyl)-3-oxopenta-1,4-dienyl]phenyl-2-methacrylate: photocrosslinking studies and reactivity ratios with vinylcyclohexane

1,5-Bis(4-hydroxyphenyl)penta-1,4,dien-3-one (HPD) was synthesized using p-hydroxybenzaldehyde and acetone in the presence of hydrogen chloride gas. Acrylated derivative of HPD 4-[5-(4-hydroxyphenyl)-3-oxopenta-1,4-dienyl]-phenyl-2-methacrylate (HPPMA) was synthesized by reacting HPD and methacryloyl chloride in the presence of triethylamine at 0-5 degreesC. Homo- and co-polymer (with vinylcyclohexane (VC)) of HPPMA was carried out in methyl ethyl ketone using benzoyl peroxide (BPO) under nitrogen atmosphere at 70 +/- 1 degreesC. All the monomer and polymers were characterized by IR and NMR techniques. Monomer reactivity ratios were calculated using Fineman-Ross (FR), Kelen-Tudos (KT) and extended Kelen-Tudos (ex-KT) methods. Photocrosslinking nature of the polymer samples were carried out in solution phase using tetrahydrofuran (THF) solvent under high frequency UV light. Rate of photocrosslinking of the polymer samples were measured for poly(HPPMA) and for poly(VC-co-HPPMA). Thermal stability of the polymer samples was recorded using thermogravimetric analysis (TGA) method. Molecular weights (M, and M-n) of the polymer samples were determined using gel permeation chromatographic (GPC) technique. (C) 2003 Elsevier Ltd. All rights reserved.