Effects of Temperature on Bonding

5 Effects of the Chemical Nature of Polymers/Polymeric Additives/ Surface Roughness 

Material properties such as the chemical nature of the polymers, their polarity, and MW, are also important in determining the bond strength. A non-polar rubber like a polybutadiene has poor adhesion to plasticised PVC, whereas introduction of a polar group like a nitrile group into BR (as in NBR) enhances the joint strength. This may be attributed to the strong dipolar interactions between the two polymers. In the case of 

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The effects of temperature on bonded films have been mentioned earlier in this chapter in connection with specific types of binder, and temperature limits are shown in Table 11.2. As a generalisation it is clear that up to 350 C in air the temperature limits are determined by the type of binder used, while at higher temperatures the thermal stability of the molybdenum disulphide is likely to be the limiting factor. However, where a soft coating has been heavily burnished, the resulting film will consist largely of molybdenum disulphide, and the thermal stability of the binder used will be less important. 

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