Effect of dicumyl peroxide and phenolic resin as a mixed curing system on the mechanical properties and morphology of TPVs based on HDPE/ground tire rubber

Abstract

Thermoplastic vulcanizates (TPVs) are a special group of thermoplastic elastomer with the characteristic that consists of rubber elasticity and the processability of thermoplastic polymers. TPVs based on high density polyethylene (HDPE)/ground tire rubber (GTR) with phenolic resin (HY-2045) and dicumyl peroxide (DCP) as vulcanizing agents are prepared through dynamic vulcanization in this article. The blends consisting of 40/60 HDPE/GTR are melt-mixed in an internal mixer and then pressed with a compression molding machine. The aim of this experiment is to study the influence of a compound curing agent system on the mechanical properties of the HDPE/GTR composites. The results indicate that the mechanical properties of the HDPE/GTR blends are improved significantly by adding 4 phr HY-2045 and 0.3 phr DCP than those of TPVs without any vulcanizing agents after dynamic vulcanization. The X-ray photoelectron spectroscopy study and the FTIR-ATR analysis confirmed that the crosslinking phenomenon occurred in the preparation of TPVs; and the gel fraction analysis indicates that the GTR components and the HDPE components of the HDPE/GTR blends are all moderately crosslinked.

Waste Rubber Recycling: A Review on the Evolution and Properties of Thermoplastic Elastomers

“…Furthermore, Kim et al [50] compatibilized acrylamide (AAm) modified GTR/HDPE blends with PP-g-MA and reported impact strength improvements of the AAm-grafted powder-filled composite compared with those of the unmodified powder-filled system and due to the bonding effect between rubber powders and the compatibiliser ( Figure 12). Similar studies also focused on using copolymers as compatibilisers in TPE blends [51][52][53][54]. For instance, Shanmugharaj et al [49] used polypropylene grafted maleic anhydride (PP-g-MA) as a compatibiliser in PP/GTR blends by using allylamine grafted GTR and reported 10-20% tensile strength improvement of the PP-g-MA containing compound compared with unmodified blends as a result of enhanced compatibility and interaction between all the components.…”

“…Furthermore, Kim et al [50] compatibilized acrylamide (AAm) modified GTR/HDPE blends with PP-g-MA and reported impact strength improvements of the AAm-grafted powder-filled composite compared with those of the unmodified powder-filled system and due to the bonding effect between rubber powders and the compatibiliser ( Figure 12). Similar studies also focused on using copolymers as compatibilisers in TPE blends [51][52][53][54].…”

Improving the properties of reclaimed waste tire rubber by blending with poly(ethylene‐co‐vinyl acetate) and electron beam irradiation

“…However, the pattern of crack was less sharp and slightly (He et al, 2014). Enhanced compatibilization between two phases can be achieved with efficient placement of radiation sensitizers in the interphase…”

Effect of Peroxide Loading on Properties of Natural Rubber and Low-density Polyethylene Composites

“…6 Use of organic peroxides for enhancing compatibility between polyethylene and ethylene vinyl acetate copolymer was successful. 7 Also, 2,5-dimethyl-2,5-di-t-butyl peroxy hexane acted as a radical coupling agent for LDPE/polypropylene (PP) blends. 8 The vulcanisation process of polymers by organic peroxides consists of three successive steps: (1) the haemolytic decomposition of peroxide and generation of free radicals; (2) the abstraction of hydrogen atom from the polymer chain resulting in stable peroxide decomposed products and polymer radicals; and (3) the combination of two polymer radicals to form a C-C crosslink.…”

“…A similar trend in tensile strength was reported for HDPE/GTR blends. 7 Elastic elongation is due to uncoiling, untwisting and straightening of chains in the stress direction and indicates an amorphous behaviour of a material. 28 Figure 7 shows an increase in elongation at break with the addition of 0.1 phpp of DCP due to the presence of a higher degree of crosslink density, confirming that the added loading is insufficient to crosslink the NR phase in the composite.…”