Studies on the preparation of multi-monomer grafted PP by one-step extrusion and the blends with PVC

Abstract

Abstract. Firstly, a novel grafted polypropylene (PP) was prepared by one step free-radical melt grafting method in a single-screw extruder. It was shown that the addition of St to the melt-grafting system as a comonomer could significantly enhance the grafting degree of MMA onto PP and reduced the degradation of PP matrix by means of FTIR and MFR tests, respectively. Then, the extruded multi-monomer grafted PP, as a component, was directly blended with poly(vinyl chloride) (PVC), denoted as gPP/PVC. The corresponding improved compatibility was examined. Due to the addition of gPP the tensile strengths of gPP/PVC blends increased significantly in comparison to pure polypropylene/poly(vinyl chloride) blends (PP/PVC), while the impact strengths remained unchanged. The DSC results also suggested that the compatibility of PP/PVC blends were improved largely.

Improvement of the dispersity of micro‐nano particles for PP/PVC composites using gas‐assisted dispersion in a controlled foaming process

“…Figure 3a shows that the strain-at-break decreases with the addition of PVC, indicating that the addition of PVC reduces the plasticity of materials. The tensile strength of PP/PVC blends also decreases with the addition of PVC, which is known to have a higher tensile strength than PP [13][14][15], especially for rigid PVC resin. Hence, the decrease in tensile strength of PP/PVC blends suggests that the addition of PVC cannot actually improve the mechanical properties of PP resin.…”

“…Blending PVC with PP also benefits the recycling of the two materials since it can partially reduce the classification of recycled materials. Meanwhile, although the polarity of the two resins is different, possibly leading to poor compatibility and a reduction in the mechanical properties of the PP/PVC blends, adding compatibilizers such as chlorinated polyethylene (CPE), PP‐g‐(St‐co‐MMA) graft copolymer, and other fillers efficiently improves the compatibility and mechanical properties . Hence, PP/PVC blends have been reported to be a type of material with complementary advantages .…”

Effects of chain extender on properties and foaming behavior of polypropylene foam

“…The radicals in PP are unstable to steric hindrance offered by the methyl groups and therefore may undergo a b-decomposition reaction, graing reaction of the monomer and a crosslinking reaction, or partial polymerization of the monomers due to side reactions. [17][18][19] Glycidyl methacrylate (GMA) is a bifunctional monomer having both an epoxy group and an acrylic group. The acrylic group of GMA participates in the graing reaction with other acrylic groups or vinyl groups, but the epoxy group remains in the polymer chain.…”

“…23 According to reported studies, the gra efficiency of GMA is best when the ratio of GMA to styrene monomer is 1 : 1. 17,21,24 Adipic acid (AA) acts as a bifunctional monomer in chain extension, with two carboxyl groups, and can be used to bond the two polymer chains having an epoxy group and a hydroxyl group. In other words, AA reacts with the epoxy group graed to the PP chain to form an ester group and forms a bond between the chains.…”

A Comparative Study of Nanosilica/Poly(propylene) Composites Prepared by Reactive Compatibilization

“…[5,6] Recently, a novel approach was developed in the authors' lab, based on the concepts of surface graft polymerization [1] and in situ reactive compatibilization. [7,8] That is, poly(glycidyl methacrylate) (PGMA) with reactive epoxide groups, was grafted onto nano-SiO 2 and then the grafted nanoparticles were melt-blended with matrix poly(propylene) (PP) and aminated PP (PP-g-NH 2 ). [9] The graft polymerization can effectively deagglomerate the nanoparticles and increase their hydrophobicity.…”