expensIV It can be manufactured into tobacco pipes, kettles, decorative boards as well as parts with xcellent electric insulation 4. Unsaturated Polyester Resins (UP) P is the compound formed by the alkyd of unsaturated binary acid and ethylene monomer. The resin is a kind liquid of low viscosity, which will not produce gas when being solidified Hence the molding pressure thereof is rather low. Intensified by glass fiber, its mechanical intensity will be much higher The substance can be used to manufacture airplane parts, ship parts, gasket for helm bathtubs, sports cars, cooling towers, troughs as well as drug boxes 5. Epoxy Resins(EP) Major raw material for epoxy resin is reacted from propylene and benzene. The substance is adhesive to other substances, especially metals, and therefore, it can be mad esives Another important feature is that it will not produce volatile substance when being solidified, and hence is of small shrinkage Endowed with such advantages it can be manufactured into molding products with excellent precision of dimension which is very stable. It can be used as adhesives and coatings 6. Polyurethanes Resin Polyurethanes resin embodies the properties of foam, rubber, thermoplastic plastics as well as d as elastor tings etc and can also adopted as synthetic fiber of large shrinkage. The substance is of high elasticity, obdurability and tensile strength, and can fight against the erosion from oil or solvent and can resist aging and It will decompose in water and cannot resist against acid, alkali, boiled water and vapor. Application 1)As foam. Due to its properties such as high elasticity, tensile strength and fatigue resistance. the substance can be used as soft foam 2)As rubber elastomer. The substance is of sound elasticity, tensile strength, rupture strer brasion resistance as well as age resistance and can be used as tires for trucks. various rollers or conveying belts and quiet gears 3)As coating and adhesive. Coatings and adhesives made from polyurethanes resin can be well adhered to the adhesive interface and can be used to adhere such materials as wood. rubber. glass and metals. It will turn yellow under ultraviolet radiation 3.2 Mold Materials Plastic mold is of multiplex varieties and specifications. Due to its complicated shapes and low surface roughness, it is rather difficult to be manufactured. Therefore, it seems very important to comprehensively analyze its working condition and performance so as to improve the service life, ensure processing quality and reduce production costexpensive. It can be manufactured into tobacco pipes, kettles, decorative boards as well as parts with excellent electric insulation. 4. Unsaturated Polyester Resins (UP) UP is the compound formed by the alkyd of unsaturated binary acid and ethylene monomer. The resin is a kind liquid of low viscosity, which will not produce gas when being solidified. Hence the molding pressure thereof is rather low. Intensified by glass fiber, its mechanical intensity will be much higher. The substance can be used to manufacture airplane parts, ship parts, gasket for helmets, bathtubs, sports cars, cooling towers, troughs as well as drug boxes. 5. Epoxy Resins (EP) Major raw material for epoxy resin is reacted from propylene and benzene. The substance is adhesive to other substances, especially metals, and therefore, it can be made into adhesives. Another important feature is that it will not produce volatile substance when being solidified, and hence is of small shrinkage. Endowed with such advantages, it can be manufactured into molding products with excellent precision of dimension which is very stable. It can be used as adhesives and coatings. 6. Polyurethanes Resin Polyurethanes resin embodies the properties of foam, rubber, thermoplastic plastics as well as thermoset plastics. It can be used as elastomers, adhesives and coatings etc and can also be adopted as synthetic fiber of large shrinkage. The substance is of high elasticity, obdurability and tensile strength, and can fight against the erosion from oil or solvent and can resist aging and abrasion. It will decompose in water and cannot resist against acid, alkali, boiled water and vapor. Application: 1) As foam. Due to its properties such as high elasticity, tensile strength and fatigue resistance, the substance can be used as soft foam. 2) As rubber elastomer. The substance is of sound elasticity, tensile strength, rupture strength, abrasion resistance as well as age resistance and can be used as tires for trucks, various rollers or conveying belts and quiet gears. 3) As coating and adhesive. Coatings and adhesives made from polyurethanes resin can be well adhered to the adhesive interface and can be used to adhere such materials as wood, rubber, glass and metals. It will turn yellow under ultraviolet radiation. 3.2 Mold Materials Plastic mold is of multiplex varieties and specifications. Due to its complicated shapes and low surface roughness, it is rather difficult to be manufactured. Therefore, it seems very important to comprehensively analyze its working condition and performance so as to improve the service life, ensure processing quality and reduce production cost