Plastic raw materials, injection molding process

First, the concept of plastic resin: the first refers to the tree to secrete fat. For example: rosin; later found that the secretion of tropical insects can also be extracted from the resin. For example: some lac; can also be obtained from petroleum resin. For example: asphalt; these are natural resins. Its characteristics: (1), no obvious melting point; (2), after heating, gradually softened; (3), soluble in organic solvents; (4), insoluble in water. Now most of the use of artificial methods to manufacture synthetic resin, which is better than the quality of the natural resin. Such as: phenolic resin (PF), epoxy resin (EP), polyethylene (PE), polyvinyl chloride (PVC), etc.. Plastic is the main ingredient of the resin, plastic is a good plasticity, which is given by the synthetic resin. Plastic is a polymer resin as the main component, in a certain temperature and pressure with plastic and flow, can be molded into a certain shape, and in a certain condition to maintain the shape of the same material. Some synthetic resins may be used directly for plastics (e.g., polyethylene, polyvinyl chloride, nylon, etc.), but some synthetic resins must be added in some of them to be used as plastics (such as phenolic resins, amino resins, polyvinyl chloride).

Two, plastic characteristics: 1, light weight; 2, excellent chemical stability; 3, excellent electrical insulation properties; 4, high strength; 5, excellent wear resistance, self lubrication and suction performance; 6, bonding ability; 7, excellent molding performance; 8, color range, can be dyed a variety of colors, 2, mechanical strength and hardness is far less than metal materials; 3, heat resistance is less than metal; 4, thermal conductivity; 5, easy aging.

Three, plastic components: according to its composition of plastic points: simple material, multiple sets of plastic; simple group of plastics basically with resin, sometimes with small amount of additives, colorants, lubricant. For example, organic glass, poly styrene; multicomponent plastic in addition to the resin, but also adding filler, increasing plastic agent, stabilizer, coloring agent, a lubricant. For example: phenolic molding powder, PVC; if in the phenolic molding powder, if there is no filler and polyvinyl chloride without stabilizer, nitrocellulose, if there is no plasticizer cannot serve as plastic, and can't process.

Multi group divided into plastic components are as follows: 1, resin, fillers; 3, increased plasticizer; 4, a colorant, and a stabilizer. 6, lubricants; also special requirements and more components need to add. For example: foaming agent, stop agent, antistatic agent, agent, agent, reinforcing agent, coupling agent, crosslinking agent, hardening agent, etc.. Four: classification of Plastics: classification methods, now more scientific method is based on the molecular structure of synthetic resin and its characteristics, will be divided into the following two categories: 1, thermoplastic: can be repeatedly heated and still has a plastic synthetic resin made of plastic; such as: polyethylene, polypropylene, polyvinyl chloride, polyvinyl chloride, organic glass, nylon, ABS, etc..