Mechanical properties, dynamic mechanical analysis and molecular cross-linking of GTR/NR re-Vulcanized blends. Issue 4 (November 2022)

• Record Type: Journal Article
• Authors: Zitzumbo, R; Alonso, S; Estrada-Monje, A; Becerra, María B; Avalos, F; Medina-Torres, L
• Is Part Of: Progress in rubber, plastics and recycling technology. Volume 38:Issue 4(2022)
• Page Start: 280
• Page End: 294
• Publication Date: 2022-11
• Subjects: Ground tire rubber -- cole-cole charts -- GTR/NR blends -- natural rubber -- DMA; Plastics -- Recycling -- Periodicals; Plastics -- Periodicals; Rubber -- Recycling -- Periodicals; Rubber -- Periodicals; Polymers -- Recycling -- Periodicals; Polymers -- Periodicals; 668.4192
• DOI: 10.1177/14777606221127370
• Languages: English
• ISSNs: 1477-7606

Abstract

The effect of natural rubber (NR) on mechanical, chemical and thermal properties of ground tire rubber (GTR) was investigated. Mechanical and thermal properties of GTR/NR vulcanized blends were determined with a universal testing machine and a dynamic mechanical analyzer (DMA). The molecular cross-linking density was determined by molecular swelling in toluene. Presents results indicate that the carbon black embedded in the GTR interior phase of the GTR/NR re-vulcanized blends, did not participate in the NR phase molecular motion restriction. The blends of GTR/NR showed the phenomenon known as reversion, leading a decreasing of the mechanical properties, that could be attributed of the degradation of the interphases (GTR/NR)n+j, j=1, 2, 3, … . On the other hand, the Cole-Cole charts of the GTR/NR vulcanized blends changed from a semicircular to an irregular form as the NR concentration increases, imposing the heterogeneity of the blend. In addition, in the Cole-Cole charts of GTR/NR vulcanized and re-vulcanized blends, the height ( E´´ ) and the width ( E´ ) of the curves decreased while the re-vulcanization processes number was greater; obtained results could be attributed to the increasing of the molecular cross-linking density.