A novel grafting‐modified waste rubber powder as filler in natural rubber vulcanizates

Abstract

Polycardanol was synthesized from cardanol, paraformaldehyde, p-toluenesulfonic acid, phosphoric acid (H 3 PO 4 ), and phosphorus pentoxide (P 2 O 5 ) via a two-step process. Results indicated that polycardanol is an acid with high molecular weight and can be self-crosslinked at high temperature. A modified WRP (MWRP) grafted by long chain can be obtained from the reaction between WRP and polycardanol. The sulfur content of MWRP is 0.27%, which is lower than that of WRP by 0.47%. The oxygen content of MWRP is higher by 13% than that of WRP. The phosphorus content of MWRP reaches 5.25%. The water contact angle of MWRP is 91.58, whereas that of WRP is 123.78. The properties of the WRP/NR and MWRP/NR composites were also investigated. MWRP/NR possesses higher tensile strength than WRP/NR because of the enhanced interfacial interaction between MWRP and the NR matrix. Post-treatment is also conducive for MWRP/NR to improve its tensile strength at high MWRP content.

Effects of modified silica on the co‐vulcanization kinetics and mechanical performances of natural rubber/styrene–butadiene rubber blends

“…Rigid fillers have been widely used and even indispensable in rubber industry for the improvement of physical strength, thermal stability, and abrasion resistance of rubber composites . It is known that the presence of the fillers including silica in rubber phase will significantly affect the crosslinking behavior of rubber chains.…”

Preparation and characterization of maleic anhydride‐grafted desulfurization rubber powder by free‐radical polymerization

“…The absorption peak of DRP at 3440 cm −1 should be the stretching vibration of OH bonds. [ 29 ] The absorptions at 2925 and 1438 cm −1 were the stretching vibration of the CH bonds and the in‐plane bending vibration of the CH bonds of saturated alkanes, respectively. [ 30–32 ] The absorption band at 1630 cm −1 was attributed to the C═C vibration absorption peak in the devulcanized rubber powder.…”

Effect of Activation Modes on the Property Characterization of Crumb Rubber Powder from Waste Tires and Performance Analysis of Activated Rubber-Modified Asphalt Binder

“…Crumb rubber after desulfurization activation could form active groups on the surface by interrupting the crosslinking bond to improve the compatibility between crumb rubber powder and asphalt [7,8]. At present, the commonly used crumb rubber powder activation methods include physical activation methods, such as the microwave method and ultrasonic method [9], chemical activation methods [9], the biological method [10], etc. In addition to the above activation methods, mechanochemical methods using chemical adjuvants are also applied to the activation of crumb rubber powder [11].…”