Synthesis, characterization and liquid crystalline properties of polyacrylates and polymethacrylates containing aryl ester pendant unit

✍ Scribed by A. V. Sesha Sainath; A. Kameswara Rao; A. V. Rami Reddy

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 344 KB
• Volume: 75
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(20000124)75:4<465::aid-app1>3.0.co;2-2

✦ Synopsis

Aryloxycarbonylphenyl acrylates and methacrylates were prepared by reacting 4-acryloyloxybenzoyl chloride and 4-methacryloyloxybenzoyl chloride with different phenols. They were homopolymerized using benzoyl peroxide as the initiator at 65°C in dimethylformamide. The polymers were characterized by IR and 1 H-NMR spectra and size exclusion chromatography. Differential scanning calorimetry and polarizing optical microscopy studies revealed that the phenyl esters of poly(4-acryloyloxybenzoic acid) and poly(4-methacryloyloxybenzoic acid) did not show any liquid crystalline properties, but, the para-aryl-substituted phenyl esters did exhibit mesophase properties in the temperature range of 98 -265°C depending on the nature of the aryl substituent. Polymethacrylates exhibit higher T g , and lower T m and T i than the polyacrylates having the same pendant mesogen. Thermogravimetric analyses have shown that the initial decomposition temperatures of the polymers are above 230°C.