The plastic resin can be divided into amorphous or crystalline. They form solid like quartz that has near-perfect structure and integrity of the crystalline order of the larger complex of very long polymer chains, thereby preventing. Polymers, such as high density polyethylene is somewhat crystalline, crystalline performance of the nylon even more strongly, while the crystallization of POM was stronger. Left some common crystal-shaped plastic and amorphous plastic. Noting that many engineering plastics in the crystalline column, such as POM, nylon and polyester. This is because the crystalline structure of the resin tends to produce engineering applications, the required characteristics, such as: anti-chemical, oil, gasoline, grease, etc.. It is the supplementary installation method of cell phone jammer on the outer wall.
Mechanical strength and hardness. At high temperatures, maintain mechanical and chemical properties unchanged. Resistance to fatigue and repeated impact. Translucent or opaque. Polymer pyramid. This diagram shows the classification of different resin. Bottom is a commodity plastics the purpose of two features, at the top of the tower is a high-performance plastics, engineering plastics in the middle position. PEI: polyimide PEEK: polyether ketone of PES: polyphenylene ether sulfone PPS: polyphenylene sulfide. PAR: polyarylate the PSU: polysulfone LCP: liquid crystal polymer of HTN: high-temperature nylon. PI: Polyimide PET: polyethylene terephthalate of PBT: polyethylene terephthalate. PC: Polycarbonate M-PPO: modified polyphenylene ether Nylon: Nylon. It is easy and convenient to supply the power for cell phone jammer .
ABS: acrylonitrile butadiene styrene copolymer. POM: POM TPE: Thermoplastic polyester elastomers PS: Polystyrene PP: polypropylene. PVC: Polyvinyl Chloride of HDPE: high density polyethylene PMMA: polymethyl methacrylate (acrylic). LDPE: Low Density Polyethylene SAN: styrene-acrylonitrile copolymer SMA: styrene maleic anhydride. DuPont crystalline engineering plastics. Crystal nature of the molding process, to destroy the melting point of crystalline order of the need for additional heat, the heat is called heat of fusion. Crystalline plastics and amorphous plastic heat of fusion of the comparison in Figure below. Amorphous substances increase the temperature to see added to the heat, but increasingly presented as the liquid. The installation method of down directional antenna of cell phone jammer on the top floor can avoid the trouble.
Before the rise in temperature to the melting point, crystalline plastic material can maintain the strength and hardness unchanged. The additional heat required to heat of fusion when melting destruction of the crystal structure, while the temperature remains constant until the melting end. With the plastic in the mold cooling, heat of fusion released from the mold out to be dissipated. However, as the temperature decreases, the molding stability and hardness, to quickly improve, the workpiece can be quickly removed from the mold. Therefore, crystalline plastic is more suitable for short-cycle molding. Compact structure means that a larger volume change from the melt to the solid crystalline plastics. Therefore, crystalline plastic amorphous plastic molding shrinkage usually the former is greater than one per cent, while the latter is about 0.5%. Of course, this kind of installation method of cell phone jammers increases the cost of the directional antenna.
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