Blending modification of Wuhan Handern polycarbonate and polyolefin
DATE：2020/6/12 8:40:35 / READ： / SOURCE：This station
Blending modification of Wuhan modern polycarbonate and polyolefin
I. OverviewPC/PO alloys include PC/PE alloys and PC/PP alloys. The blending of PC and PO can improve the impact resistance of PC, improve the processing fluidity of PC, reduce the internal stress of the product, and also increase the tensile strength and elongation at break of PC, and reduce the cost of PC. www.handern.com Cast film equipment Adding PE to PC can improve the thick wall impact resistance of PC. Blending PC with a small amount of PE can increase the impact strength of PC by 4 times, the melt viscosity decreases, and the tensile strength and bending strength remain almost unchanged. www.handern.com Cast film equipment PC is blended with 15% PP, the alloy's impact strength is higher than that of PC. www.handern.com Cast film equipment PC/PO alloys have commercialized products abroad. The impact strength of these products is high, especially the impact strength of the cantilever beam is 4 times higher than that of PC, and it can withstand high temperature sterilization, easy processing, and fluidity. Good, resistant to boiling water, resistant to stress cracking, suitable for making food cutlery, containers, safety helmets, electrical parts, power tool shells and weft tubes for textiles, etc. www.handern.com Cast film equipment
The solubility parameters of PC and PO are quite different, and they belong to polar and non-polar polymers, respectively, and there is a certain polarity difference between the two. www.handern.com Cast film equipment In addition, PC is a non-crystalline polymer, while PO is a semi-crystalline polymer, the crystallization of the two is different. Furthermore, the flow temperature difference between PC and PO is also large. Due to the differences between PC and PO in the above aspects, PC/PO is an incompatible system. However, a small amount of PE (<10%) blended with PC can increase the notched impact strength of the PC, greatly reduce the melt viscosity, and have almost no effect on the other properties of the PC. www.handern.com Cast film equipment However, when the PE content is high, due to the incompatibility of the two components, when the two are simply blended, the morphology and structure of the blending system is difficult to control, the physical and mechanical properties of the material are unstable, and the product is divided Layer, losing use value. www.handern.com Cast film equipment Therefore, improving the compatibility of the PC/PO system is the key to obtaining a PC/PO alloy with excellent performance. There are two compatibilization technologies for PC/PO alloys, namely reactive compatibilization and compatibilizer addition.
Reactive compatibilization is to graft-modify PO first, in which polar groups that can react with PC are introduced, and then blended with PC. During the blending process, in-situ compatibilization is achieved to improve the two phases Interface adhesion. Polar monomers are carbonyl or epoxy compounds, such as maleic anhydride/glycidyl methacrylate and so on.
The non-reactive compatibilizer of the PC/PE alloy is mainly a binary or ternary copolymer formed by ethylene and a polar compound containing a carboxyl group or an epoxy group. The compatibilizer is used-one end is compatible with PE, and the other end is compatible with PC has the characteristics of interaction or reaction to improve the compatibility of PC/PE alloy. www.handern.com Cast film equipment These copolymers are mainly EVA, MIBS, ethylene methacrylic acid copolymer or its sodium salt ionomer. Compatibilizers for PC/PE alloys can also choose block copolymers with a structure similar to PE at one end and a structure similar to PC at the other end, such as SEBS and SBS.
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