The main business of Taihua plastics division is polystyrene (PS), ABS, ASA, San (styrene acrylic co polymer), polypropylene (PP), polycarbonate (PC) and so on Due to the active market expansion and the completion of the upstream raw material plants of Liuqing, the manufacturing and sales of PC / ABS and other comite adhesives have formed a strong integration between upstream and downstream. Looking forward to the future, the marketing of our products is expected to continue to grow. We hope that the company's products can provide reliable quality, stable material source and reasonable price of high-quality raw materials and technical support for China's plastic downstream processing industry, and jointly improve the overall situation To strive for the competitiveness of the industry.
PP的优点:
PP虽然比回收PE有较高的机械强度和模量,但是像新PP树脂一样,回收PP的耐冲击性能尤其是耐应力开裂性能差,且低温性能差。这些性能特征是由PP聚集态结构和大分子链构造决定的,因此可用聚乙烯进行改性。回收PE(LDPE、HDPE)与收PP制共混物时,如果PP回收料比较多,可以直接制备合金,如在PP 中掺人10%一25%HDPE,其改性后的共混物在—20℃时落球冲击强度比PP提高8倍以上,而且加工流动性增加,可适用于大型容器的成型。从结构上来说PE的加入破坏了PP的结晶如大球晶碎化,也降低了PP的结晶度;若在体系中再加入EPDM。约5%可提高PP与PE的相容性,强度得到提高;加入少量EPR橡胶也可提高材料的冲击性能。
The tensile strength and rigidity of PP are good, but the impact strength is poor, especially at low temperature. In addition, if there is orientation or stress in the molding process, the impact strength will be significantly reduced. Although the impact strength is poor, its mechanical properties can compete with high cost engineering plastics in many fields after filling or strengthening. The surface hardness of PP is lower than that of PE. When the crystallinity is high, the hardness also increases, but it is still lower than PVC, PS, ABS and so on. Among the five general plastics, PP has the best heat resistance. PP plastic products can work at 100 ℃ for a long time. Without external force, PP products will not deform when heated to 150 ℃
The comprehensive properties of PP are better than that of PE. PP products are light in weight, good in toughness and good in chemical resistance. Disadvantages of PP: low dimensional accuracy, insufficient rigidity, poor weather resistance, easy to produce "copper damage", it has the phenomenon of t shrinkage, easy aging, brittle, easy deformation after demoulding. In daily life, the commonly used fresh-kee box is made of PP material. In order to prevent photoaging, it is necessary to add UV absorber into PP, which can transform the UV absorption of 290 ~ 400nm into non destructive long wavelength light. For the PP plastic products buried in the soil or used indoors in the dark, only the main and auxiliary antioxidants can be added, and the ultraviolet absorber is not needed. The shrinkage and crystallinity of PP are lower than that of PE. PP has a certain permeability to oxygen, carbon dioxide and water vapor. Compared with nylon PA and polyester PET, PP is much worse than nylon PA and polyester PET, but it is much worse for high barrier plastics such as PVDC and EVOH. But compared with other non plastic materials, its air tightness is quite good. The air tightness can be greatly improved by adding barrier materials or coating barrier plastics on the surface. PP is a non-polar polymer with good properties
PP的化学稳定性优异,对大多数酸、碱、盐、氧化剂都显惰性。例如在100℃的浓磷酸、盐酸、40%硫酸及其它们的盐类溶液中都是稳定的,只有少数强氧化剂如发烟硫酸等才可能使其出现变化。PP是非极性化合物,对极性溶剂十分稳定,如醇、酚、醛、酮和大多数羧酸都不会使其溶胀,但在部分非极性**溶剂中容易溶解或溶胀