Application of Experimental Design for Optimization of Interfacial Adhesion between Rubber and Surface Modified Polyester Fabric-Factory Experience

Tires and conveyor belts are among the most prominent examples of cord-rubber composites in which, synthetic fibers are extensively used as reinforcing material. Although, it passes a long time from utilization of cord-rubber composites in rubber industry, yet, adhesion of cord to rubber remains an important challenge in this area, as it determines the quality of the final product. Accordingly, present work attempts to optimize adhesion of dipped Polyester/Polyamide 66 fabrics through identification and controlling of effective process parameters by the means of Design of Experiment (DoE). To accomplish this target, fractional factorial design, \({2}_{IV}^{7-2}\), has been implemented with seven process parameters, namely, Styrene-Butadiene-Rubber (SBR) content, curing temperature and time, type and thickness of fabric, Dip Pick Up and type of adhesive in two variation levels. Subsequently, 32 experiments have been carried out through 4 blocks. Analyze of experiments showed that curing temperature and activation of fabrics/fibers before dip coating are the most important factors on adhesion of cord to rubber. The quality of fitting in applied model has been, eventually, checked using additional experiments. Pairwise Pearson Correlation coefficient demonstrated strong linear correlation between calculated data from the model and corresponding test results in laboratory.