Gradient Density Grafted Polymers on Ground Tire Rubber Particles by Atom Transfer Radical Polymerization

Abstract

Summary: The graft polymerization of styrene and (meth)acrylic monomers via ATRP from cross‐linked rubber particles, produced by recycled tires (“ground tire rubber”, GTR), is reported. GTR particles, obtained by cryogenic grinding process, still contain CC unsaturations on the surface, which were first oxidized to hydroxyl groups and then modified by reaction with 2‐bromoisobutyryl bromide to serve as ATRP macroinitiators. Graft polymerizations were carried out using CuBr/CuBr2/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalytic system in bulk or in anisole at high temperature. The grafted particles were analyzed by ATR‐IR (spectra were recorded on particles surface and cross‐sectional slices), TGA, SEM and X‐ray microanalysis.Arrangement of surface‐grafted polymer assemblies along the particles section.magnified imageArrangement of surface‐grafted polymer assemblies along the particles section.

Mechanical and dynamic mechanical properties of natural rubber blended with waste rubber powder modified by both microwave and sol–gel method

“…Through these methods, three‐dimensional network of WRP is cut off and WRP can be easily compatible with the virgin rubber during compounding. The latter group mainly contains grafting method14–17 and sol–gel method 18. Compared with the former group, the latter technique does not break the three‐dimensional network and sometimes provides WRP with some particular properties.…”

Preparation and characterization of a core‐shell impact modifier based on (Acrylates and styrene)‐grafted ground tire rubber and its poly(vinyl chloride) composites

“…Reuse of waste rubbers may be a good choice to solve the above problems. Much research has also been done to develop new methods to recycle waste rubbers during the last several decades . Usually, waste rubbers are first shattered under liquid nitrogen atmosphere to yield ground tire rubber (GTR) with a size range of 150–400 μm.…”

“…Second, GTR is blended with polymer matrixes directly or after surface treatments to save raw materials or enhance the impact performance of the polymer matrixes. For example, Coiai and coworkers have recently reported a novel gradient density polymer grafted GTR (GGTR) by atom transfer radical polymerization . Shanmugharaj's group has also successfully synthesized an allylamine GGTR .…”

Surface Modification of Waste Tire by Grafting with Styrene and Maleic Anhydride

“…Surface graft polymerization is important because it can provide materials with tailored properties for practical application. The ground tire rubber particles can be modified by grafting with styrene and acrylate [11]. Zhang et al, show that the grafted styrene onto waste rubber powder form core-shell structure [12].…”