Polyester/glass, laminates

Some typical properties of polyester-glass laminates are given in Table 25.1. From these figures it will be seen that laminates can have very high tensile strengths. On the other hand some laminates made by hand lay-up processes may have mechanical properties not very different from those of thermoplastics such as the polyacetals and unplasticised PVC. 

The most desirable features of polyester-glass laminates are ... 

The dough moulding compounds were originally developed in an attempt to combine the mechanical properties of polyester-glass laminates with the speed of cure of conventional moulding powder. In spite of their somewhat high cost they have now established themselves in a number of applications where a mechanieally strong electrical insulant is required. 

Polyester glass laminates (with 2% methacrylate monomer)... 

The Arrhenius treatment has been applied to aging studies on rubber (13), to predict the life of a polyester-glass laminate (14), to predict product stability of a thermosetting resin alone and in combination with two additives (15), in permanence tests on paper (16), to multi-component systems in which the principal component is paper (17), and to study the influence of temperature on the relative contributions of the oxygen-independent and oxygen-dependent processes to the total rate of newsprint deterioration (18-20). 

TABLE 4.11 Typical Properties of Polyester-Glass Laminates... 

The most frequently encountered emissions in plastics processing are probably solvents (from adhesives and paints) and styrene monomer (from polyester/glass lamination). There may be a health hazard from curing agents aliphatic amine-types can cause serious irritation (even burns) and there is also a serious rash/ asthmatic-type response. Liquid organic peroxides, such as MEKP, should be treated with extreme caution. They are sensitive to heat, are themselves combustible and will promote combustion. 

Most thermosetting materials are available in two forms, ie resins and moulding compounds. The resins may be used alone as in encapsulation processes but they are normally used in conjunction with other materials. The resins may be used with reinforcement, eg polyester/glass laminates, or with fillers and reinforcement, eg moulding compounds. This differs from the thermoplastic field where, generally, the polymeric material is used without fillers and/or reinforcement. 

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