Polymers in Building and Civil Engineering

PVC is also used in windows and rooflights. Transparent PVC is much less durable than the white pigmented form described above. As a result of photooxidation, catalysed by UV light, the impact resistance steadily decreases over a period of several years with associated discolouration. UV absorbers have some protective effect but complex synergistic combinations of antioxidants and stabilisers are used to 

Polymers are used in much less obvious but often very important engineering applications. A major hidden use of polymers is as adhesives. The traditional glues were of course polymers derived from natural products. Some of the best of these still survive but synthetic polymer chemistry had led to very significant advances, particularly in the development of hot-melt adhesives that do not require solvents for their application. Another important development is the reactive adhesives based on ethyl cyanoacrylate  

Polydiene rubbers were used for many years in low voltage electrical insulation because of their low electrical conductivity and flexibility. However, the traditional rubbers degrade by peroxidation relatively rapidly even when stabilised with antioxidants. This frequently leads to fires due to electrical shortage and, in recent decades, they have been largely replaced with saturated elastomeric materials e.g. EP rubbers 

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