A common additive for recycled plastic2017.08.03 14:22
(1) Filler: Many fillers packing up the enhancement effect and plastic modification, an important part of the preparation of composite materials, such as graphite, aluminum sulfide, asbestos fiber and glass fiber, etc.; Also called filler or filler. Packing in plastic of material accounts for about 40% one 70%, commonly used fillers have wood powder, talcum powder, diatomite, lime stone powder, aluminum powder, carbon black, mica, aluminum sulfide, asbestos, glass fiber, etc. The fiber packing increases the structural strength of the plastic. Asbestos packing can improve the heat resistance of plastics. Mica stuffing can enhance the electrical insulation of plastics. Graphite and aluminum disulfide packing can improve the friction and wear resistance of plastic. In addition, because fillers are generally cheaper than synthetic resins, the addition of packing can reduce the cost of plastic.
(2) Curing: also called hardener or curing agent. Its role is to make through crosslinking resin has size mesh structure, become more rigid and stable rubber products, different kinds of resin should use different kinds of curing agent. In phenolic resin, for example, six methylenediamine is added to the epoxy resin, and the ethylene diamine and maleic anhydride.
(3) Plasticizer: in order to improve the plasticity and elasticity of plastic in processing,Add a small amount of plasticizer to the production process of plastic products. Plasticizer is usually a solid or liquid organic compound with less volatile molecular weight. They are mainly lipid and ketones, and they are commonly used to have phthalates, dioctyl phosphite, dimethylene phosphate, adipate, diphenylketone, etc. PVC resin, for example, adding phthalic acid dibutyl ester, can make the plastic becomes soft and elastic, but research has shown that it can be for experimental animal reproductive organs, blood, kidney, lung, liver and other organ damage, especially in pregnant women and developing kids is sensitive to its poison effect.
(4) Stabilizer: artificial turf in the process of processing and use, due to the effect of heat, light, oxygen, premature degradation occurs, the phenomenon such as oxidation chain scission, crosslinking, make the material performance deteriorate. In order to prevent the action of heat and light can make plastic fiber premature aging and join a small amount of stabilizing role of substances, for example, adding phenol and amine can organic matter such as antioxidant, carbon ink can be used as a uv absorber; Thermal stabilizer is the most commonly used additive in plastic products except plasticizer. In general, the seeds of epoxidation or vegetable oils such as soybean oil (ESBO) is widely used in plastic food packaging materials such as thermal stabilizer, lubricant, and plasticizer, etc. Polyvinyl chloride, polyvinylidene chloride and polystyrene usually contain 0.1-27% of epoxy-treated vegetable oils. Due to the toxicity of ethylene oxide in vegetable oil, the purity of oil will directly affect its toxicity. Usually, the greater the molecular weight (the smaller the solubility), the weaker the toxicity.
(5) Flame retardant: the effect is to prevent combustion or cause self-extinguishing, the more mature flame retardant has the inorganic substance such as antimony oxide, etc.
(6) Colorant: to make plastic a particular color and gloss, add a stain. The colorant is divided into dyes and pigments by its solubility in the shading medium. Dyes are organic compounds that dissolve in colored resin; Pigments for inorganic compounds commonly, insoluble in the medium being shaded, its color is by itself the high dispersion particles dispersed in dyed medium, the refractive index difference is big, and matrix to absorb part of the light, and another part of the reflected light, give a person with color vision. Pigment is not only the color of plastic, but also the function of filler and stabilizer. In addition, according to the construction plastic use and the need in molding, sometimes also add lubricants, antistatic agent, foaming agent, flame retardant and anti-mildew agent etc.