Abstract
The polymer composite was prepared from the wastes of natural rubber glove (NRG) and polystyrene foam (PSF) blended with cellulose from sugar cane leaves via the laminate method. The NRG and PSF were firstly dispersed in toluene under continuous stirring. Then, maleic anhydride (MA) was added into the mixture. Effects of blend ratio and of MA content (0.5–15%, w/w) on physical properties of the polymer composite were investigated. The toluene resistance of the polymer blend was improved after adding MA and cellulose. The highest toluene resistance was achieved when using 12% cellulose. The chemical reactions of MA with polymer blend and with composite were confirmed by ATR-FTIR. The hardness of the polymer blend and composite increased as a function of PSF. In addition, their impact strength increased with increasing NRG and cellulose contents.
The financial accounts of a European guayule commodity chain model were established from data acquired from previous guayule trials carried out in southern Europe. We developed a guayule commodity chain managed by a farmer for growing biomass, and a processor for extracting rubber and other byproducts (resin, bagasse) in a conceived processing plant. Different simulations were tested to find the most feasible scenario. Based on a 10-year field cultivation period, the breakeven point for the farmer was reached at 214€ ton−1 of dry biomass with an average cost of field cultivation of 1924€ year−1. By purchasing biomass at farmer's breakeven point and considering latex as the only final product, the processor breakeven point was reached at latex selling price of 8.16€ kg−1 of dry rubber. Otherwise, when adding the parallel production of crude rubber, resin and bagasse through biorefinery process, the latex breakeven point can be lower, at 2.46€ kg−1 of dry rubber (plus crude rubber at 2.15€; resin at 2.10€; bagasse at 0.10€); all prices far below current market prices.
Guayule in the Mediterranean was compared to other crops showing that it can play a role as an alternative crop from which the region can benefit to improve its economic development.