Polypropylene / polyvinyl chloride blend modified breathable film production line
日期：2021/7/27 8:34:50 / 閱讀： / 來源：本站
Polypropylene / polyvinyl chloride blend modified breathable film production lineIn the past, people always thought that PP and PVC could not be blended, so there were few reports in this field. However, with the development of polymer materials science, it is recognized that polymers with large compatibility can produce blends with excellent properties through specific blending technology, and can highlight their respective characteristics, so people attach great importance to them. Breathable film production line www.www.dressup9x.com
PP and PVC are two resins with different polarity. The interfacial tension between their blends is large and the adhesive force between the interfaces is small. Therefore, compatibilizers must be used. MPP can be used as compatibilizer of PP / PVC blends, and can improve the physical, mechanical and processing properties of the blends. It is also an effective compatibilizer for recycling waste PP and PVC. When the melt temperature of twin-screw extruder is controlled at 180 ~ 185 ℃, PP / PVC blend can be extruded and granulated with good properties. Breathable film production line www.www.dressup9x.com
Hyperbranched polymer (HBP) is a kind of highly branched macromolecules with three-dimensional quasi spherical structure. It can be used to increase the compatibility of PP / PVC blends because of a series of unique physical and chemical properties such as low melt viscosity, good solubility and a large number of terminal active groups. The carboxyl group of MAH in PP-g-MAH reacted with the terminal hydroxyl group of Hyperbranched Poly (amide ester) to obtain PP Grafted hyperbranched poly (amide ester) (pp-hbp). PP / PVC blends were compatibilized with pp-hbp to improve the mechanical properties and compatibility of the blends. Breathable film production line www.www.dressup9x.com
When pp-hbp was added to PP / PVC blend, the tensile strength increased. When pp-hbp reached 5 phr, the tensile strength reached a maximum, which was 18.0% higher than that without pp-hbp compatibilizer. This shows that the addition of pp-hbp does play the role of compatibilizer. A small amount of pp-hbp can significantly improve the compatibility and mechanical properties of the blends. Because the amide and ester groups in HBP interact with methylene chloride atoms on PVC segments to form weak hydrogen bonds, the tensile strength of samples B and C increases. However, when the amount of pp-hbp exceeds 5 phr, the tensile strength decreases. This is because the mechanical properties of HBP in pp-hbp are poor, so the tensile strength begins to decrease after reaching the maximum value.
When pp-hbp was added to PP / PVC, the notch impact strength changed little, but the maximum value also appeared when 5 parts of pp-hbp were added. In the PP / PVC blend without pp-hbp, the PVC dispersed phase particles are large and uneven, and the two-phase interface contact area is relatively small. This shows that the compatibility between PP and PVC is poor, the interfacial bonding is very weak, PVC is difficult to be evenly dispersed in PP matrix, and the size of dispersed phase is large. In the PP / PVC blend system with 2 parts of pp-hbp, the size of PVC dispersed phase decreases and the number of particles increases accordingly, indicating that the compatibility between PP and PVC is enhanced and the tensile strength is also increased. In the PP / PVC blend system with 5 parts of pp-hbp, it was observed that the PVC particles further decreased and the number increased, and some layered morphological structures appeared, indicating that the interfacial bonding strength was further improved. In the PP / PVC blend system with 10 parts of pp-hbp, the size of PVC dispersed phase particles decreased significantly, some lamellar morphology disappeared, and dispersed evenly in the PP matrix, showing a good interface state, indicating that pp-hbp can effectively improve the compatibility of PP / PVC. Breathable film production line www.www.dressup9x.com
When 1 part of HBP is added to PP / PVC / pp-g (st co MMA) (mass ratio 80:20:6), the compatibility of the blend system can be improved, the tensile strength of the blend can reach the maximum value, and the apparent viscosity of the melt can reach the small value. This shows that the mechanical properties of the blends can be improved by adding HBP to the blends. Breathable film production line www.www.dressup9x.com