Details

Autor(en) / Beteiligte

• Han, Hui-jing
• Zhang, Sha
• Sun, Ru-yi
• Wu, Jian-hua
• Xie, Mei-ran
• Liao, Xiao-juan

Titel

Photocrosslinkable Polynorbornene-based Block Copolymers with Enhanced Dielectric and Thermal Properties

Ist Teil von

• Chinese journal of polymer science, 2016-03, Vol.34 (3), p.378-389

Ort / Verlag

Beijing: Chinese Chemical Society and Institute of Chemistry, CAS

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Block copolymers poly（endo-N-3,5-bis（trifluoromethyl）biphenyl-norbornene-pyrrolidine）-block-poly（exo-N-（cinnamoyloxyethyl）-7-oxanorborn-5-ene-2,3-dicarboximide）（endo-PTNP-b-exo-PCONBI） and poly（exo-N-3,5-bis（trifluoromethyl）biphenyl-norbornene-pyrrolidine）-block-poly（exo-N-（cinnamoyloxyethyl）-7-oxanorborn-5-ene-2,3-dicarboximide）（exo-PTNP-b-exo-PCONBI） were synthesized by ring-opening metathesis polymerization. The endo- or exoPTNP served as the high dielectric functional chain, and exo-PCONBI acted as the crosslinking segment. The endo-PTNPb-exo-PCONBI, in which endo-PTNP has a high content of trans double bond and adopts isotactic configuration, shows a dielectric constant（？） of 15.5, whereas exo-PTNP-b-exo-PCONBI, in which exo-PTNP has 67% trans double bonds and atactic microstructure, displays relatively low ？ of 7.1. The cinnamate groups in exo-PCONBI were crosslinked to form three-dimensional network by cycloaddition reaction under UV irradiation. Exposed to UV-light for 10 min, the cinnamate group in polymer films has a crosslinking conversion of 36%, as determined by UV-Vis absorption measurements. By photocrosslinking, the polymer film has an increased ？ of 16.6, a dielectric loss of 0.03, an elevated glass-transition temperature of 137 ？C, and an enhanced decomposition temperature of 405 ？C, compared to those of polymer films without irradiation.