Methods of testing plastics. Glass reinforced plastics. Determination of volatile matter and resin content of synthetic resin-impregnated textile glass fabric|Glass, Plastics, Composite materials, Chemical analysis and testing, Determination of content, Cloth, Glass fibres, Textile glass, Testing conditions, Plastics and rubber technology, Dimensions, Gravimetric analysis, Impregnated materials, Reinforced materials, Test specimens, Volatile matter determination, Polymers