Thermal decomposition characteristics of Alder-ene adduct of diallyl bisphenol A novolac with bismaleimide: effect of stoichiometry, novolac molar mass and bismaleimide structure

Direct, efficient, organic solvent- and catalyst-free synthesis of a series of polyphosphates was accomplished. The reaction involved a gas-liquid interfacial polycondensation between arylphosphoric dichlorides and bisphenol A. The polyphosphates were characterized by IR, 1H NMR, 31P NMR, inherent viscosity, thermal analysis, and molar mass. Yields in the range 70-90 % and inherent viscosities in the range 0.30-0.40 dl/g were obtained. The thermal stability of the polyphosphates was investigated by using thermogravimetry.

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High-Temperature Adhesives Based on Alder-ene Reaction of Diallyl Bisphenol a Novolac and Bismaleimide: Effect of BMI Structure and Novolac Molar Mass

Polymers and Polymer Composites ◽

10.1177/096739110301100406 ◽

2003 ◽

Vol 11 (4) ◽

pp. 311-320 ◽

Cited By ~ 3

Author(s):

C. Gouri ◽

C.P. Reghunadhan Nair ◽

R. Ramaswamy

Keyword(s):

Bisphenol A ◽

High Temperatures ◽

Molar Mass ◽

Adhesion Properties ◽

Ene Reaction ◽

Network Polymers ◽

Lap Shear ◽

Higher Temperature ◽

Stable Network ◽

Good Retention

Diallyl bisphenol A formaldehyde novolac (ABPF) resin was cured with four structurally different bismaleimides (BMIs) at high temperatures through an Alder-ene reaction which resulted in thermally stable network polymers. The adhesive characteristics of the different BMI-ABPF systems were evaluated in terms of the lap shear strength (LSS) on aluminium substrates at varying temperatures up to 250°C. The LSS properties were not significantly affected by the structure of the BMI. Although the LSS of BMI-ABPF systems per se were not particularly high due to the brittle nature of the cross-linked structures, all the systems exhibited remarkably good retention of LSS at high temperatures. Replacing ABPF with its monomeric analogue i.e. o,o′- diallyl bisphenol A (DABA) resulted in better adhesion, but in a poorer thermo-adhesive profile. Comparison of DMA and thermo-adhesive profiles implied that in the majority of the cases molecular relaxations at higher temperature are conducive to matrix toughening which results in enhanced adhesion properties.

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Migration Characteristics and Degradation Kinetics of Bisphenol A

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.128 ◽

2016 ◽

Vol 850 ◽

pp. 128-136

Author(s):

Zhuo Jun Sun ◽

Jian Gao ◽

Hui Liu ◽

Shu Zhen Pan ◽

Shu Li Zhang ◽

...

Keyword(s):

Thermal Decomposition ◽

Bisphenol A ◽

Aging Time ◽

Degradation Kinetics ◽

Heat Stability ◽

Gas Chromatography Mass Spectrometry ◽

Oxidative Aging ◽

Before And After ◽

Thermal Oxidative Aging ◽

Kinetics Of

This paper study the migration characteristics and degradation kinetics of bisphenol A using TGA - gas chromatography - mass spectrometry and found that bisphenol A polycarbonate in the thermal oxidative aging conditions of 130 °C de-gradated to bisphenol A. At the range of 0 h to 120 h, the bisphenol A content of environmental hormones increased with time. When it reached 120 h, bisphenol A environmental hormone content decreased slightly with aging time. The content of bisphenol A reached 495mg/kg when the thermal oxidative aging time was 168 h, which was decreased compared to the content of 442mg/kg at 120 h. Polycarbonate thermal decomposition kinetics study showed that the thermal decomposition of polycarbonate can be divided into three phases. The first thermal decomposition occurred at the range of 415° C to 425 ° C, the polycarbonate end groups fracture of the second stage at 493.6°C , the main fracture of the main chain rearrangement and crosslinking, and the third stage at 598.7°C, the degradation of the chain continues to decompose and the decomposition of the crosslinked carbon precursor; thermal oxidation aging of polycarbonate decreased the heat stability and promote the thermal decomposition of polycarbonate. Comparing the oxidation induction period, thermal weight loss rate and activation energy of polycarbonate before and after thermal oxidative aging, it c found that the thermal stability of the hot oxygen aging of polycarbonate is reduced.

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