Availability thermal degradation

PEI resins reinforced with up to 40 wt % fiber glass are available. The American Cyanamid Co. uses an Ultem-type resin with carbon fibers to form their Cypac 1000 series prepregs (31). The moisture content of the resin must be less than 0.05% prior to melt processing to minimise thermal degradation. 

In contrast to the extensive work of the pure thermal degradation of polymers, less fundamental chemical information is available on the mechanism of oxidative degradation of polymeric materials. As another point of... 

Because of its fundamental role as a precursor of vitamin A and the availability of P-carotene standard in crystalline form, the thermal degradation of P-carotene in model systems has been a subject of intense research. 

The thermal degradation of alkylbenzene sulfonates in alkaline media is important because of the application at elevated temperatures. The half-lives, with respect to thermal degradation, of several commercially available sulfonates were estimated at hundreds to thousands of years at 204° C. The degradation mechanism was predominately a clipping of the alkyl chain to yield an alkylbenzene sulfonate with the phenyl group attached to the a-carbon however, desulfonation also occurred [1624]. 

The thermal degradation of B-trianilinoborazine, when conducted in ammonia even below 215°C, produced 87.7% of the available aniline. This was brought up to 92.3% by further pyrolysis at 275-299 C which compares with the maximum of 53% observed under... 

Summarising the data available at this stage, the thermal degradation of melamine borate can be represented by the scheme ... 

The use of aliphatic monomers for hyperbranched polyesters has been debated because aliphatic monomers are said to be prone to thermal degradation reactions such as decarboxylation, cyclization, or dehydration [77]. The only commercial hyperbranched polymer is a hydroxy-functional aliphatic polyester, Boltorn, available from Perstorp AB, Sweden. 

Recently, MS combinations have been available including the thermogravimetric analysis mass spectroscopy (TG-MS) combination developed by Carraher that allows the continuous characterization of evolved materials as a polymer undergoes controlled thermal degradation. 

Kinetic data on the thermal degradation of ABS and PC/ABS blends are available (130,131). Thermogravimetric analysis suggests that the kinetics of the thermal degradation can be modelled by an auto-catalytic process. 

The general melting characteristics can be established on a Fischer-Johns block or, in a more refined fashion, in a differential thermal analyzer. Should the DTA be available, it can be used on milligram quantities to define not only the melting behavior but also the temperature level and rate of thermal degradation. 

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