Study of the miscibility and mechanical properties of NBR/HNBR blends

Evaluating the efficiency of functionalized zinc oxide based curing system for polychloroprene composites and analyzing its effect on curing, physical, and morphological properties for the application in specialty power transmission belts

Polychloroprene rubber (CR) is one of the most abundantly used elastomer in power transmission belt section due to its excellent oil resistance, weather resistance, antistatic and dynamic properties. However, due to the negative impact of Zinc Oxide (ZnO) used with CR rubber towards marine environment, it is necessary to minimize the use of ZnO in CR based rubber compounds. Functionalized-ZnO(F-ZnO) being emerged as a suitable replacement for regular ZnO in rubber compounding, the effect of F-ZnO on the curing, mechanical and morphological properties of polychloroprene (CR) based composites to use in power transmission belt applications are evaluated in this work. The curing properties of F-ZnO based composites were characterized using various techniques and results were reported as a comparison with the properties of conventional ZnO (C- ZnO) based CR composites. Properties of various ZnO were analyzed using X-ray Diffraction (XRD) analysis and Field-Emission Scanning Electron Microscopy (FESEM) studies. The replacement of C-ZnO with F-ZnO help to reduce 80 % of Zn content from the end products without effecting the cure time and cross-link density of the same. 5 PHR of C- ZnO from regular compound is replaced with 1 and 3 Phr of F-ZnO and its effect on power transmission belt properties were analyzed thoroughly.

Increasing secondary and renewable material use: a chance constrained modeling approach to manage feedstock quality variation

The increased use of secondary (i.e., recycled) and renewable resources will likely be key toward achieving sustainable materials use. Unfortunately, these strategies share a common barrier to economical implementation - increased quality variation compared to their primary and synthetic counterparts. Current deterministic process-planning models overestimate the economic impact of this increased variation. This paper shows that for a range of industries from biomaterials to inorganics, managing variation through a chance-constrained (CC) model enables increased use of such variable raw materials, or heterogeneous feedstocks (hF), over conventional, deterministic models. An abstract, analytical model and a quantitative model applied to an industrial case of aluminum recycling were used to explore the limits and benefits of the CC formulation. The results indicate that the CC solution can reduce cost and increase potential hF use across a broad range of production conditions through raw materials diversification. These benefits increase where the hFs exhibit mean quality performance close to that of the more homogeneous feedstocks (often the primary and synthetic materials) or have large quality variability. In terms of operational context, the relative performance grows as intolerance for batch error increases and as the opportunity to diversify the raw material portfolio increases.