Evaluation of natural rubber latex film properties by dipping process

Abstract

Products dipped from natural rubber latex (NRL) are commonly used worldwide such as medical gloves, household gloves, condoms, mattress, etc. thanks to their mechanical properties and good biodegradability. In medical glove products, protein allergy and low quality are concerned problems. Therefore, the reduction of protein content and improvement of the characteristics of gloves with high elasticity, tensile and tear resistant properties are being studied further. NRL is an important factor affecting the product properties. In this study, four different types of NRLs with low protein content were chosen to investigate the influence of film dipping process such as the sample incubation days, vulcanization time, vulcanization temperature and curing system content to the solution viscosity, the properties of the film following ASTM D412:2004 and D624:2004 standards. The results show that the films with a thickness of less than 0.4mm and highest mechanical properties were achieved after 6 days of incubation, one time of 15-second dipping, 45 minutes of curing at 90oC, in which, NRL type 3 (23,667 N/mm2) had 6-12% higher mechanical properties than the others. The strain of the samples reached 960-1130% which was much higher than the standard (650%) making it convenient to use gloves.