Strength bond, degradation reactions

In a previous study we established that classical peroxydes could not play the major role in interfacial bonding. Bulk reactions, especially in polystyrene matrix, lead to chain degradation and related decrease of mechanical strength. Therefore,... 

As the key degradation reaction is main chain scission in most polymers, the activation energies for degradation in a particular environment are strongly dependent on the strength of the weakest bonds in the polymer backbone. Thus polymers with simple... 

Carbonylation reactions encompass a diverse set of transformations used to synthesise many important high-value fine chemicals, synthetic intermediates and materials such as polycarbonates [36]. Palladium catalysts modified with PRj ligands facilitate these reactions. However, carbonylation often requires harsh conditions, especially for less reactive C-X bonds, thereby promoting catalyst degradation via P-C bond cleavage. The strength of the NHC bond may demonstrate the utility of... 

The significance of such degradation is realized when one considers that any reaction which randomly breaks one carbon—carbon bond per thousand bonds in the polymer would reduce the average molecular weight by one-half (23). This effect would be observable in properties such as melt viscosity, tensile strength, and bulk modulus. 

One concludes that when room temperature curing systems are to be used as adhesives, the assemblies should be joined quickly to preclude various reaction mechanisms from taking place that could degrade the strength of the final bond. 

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