Properties of Carboxylated Nitrile Latex Film with Varying Thickness

摘要

Increasing price of raw materials and operational cost have triggered glove manufacturers to produce gloves with fewer amounts of material while meeting the minimum requirements for the intended application. Examination gloves in particular, are getting thinner from approximately 7 to 9 grams to 3 to 5 grams. In this study, the physical properties of latex films made from carboxylated acrylonitrile butadiene latex (XNBR), a typical base material for an examination glove, are assessed to elucidate any differences due to the thickness of the film. XNBR latex films of different thicknesses were prepared at a laboratory scale. The XNBR latex was compounded with a varying dosage of zinc oxide (ZnO) to vary the expected ionic crosslink density of the films. The mechanical properties of these films were evaluated. This study confirmed that with increasing loading of ZnO, the physical properties specifically, the tensile strength and the modulus values increased, while the extension tended to be lower and tear strength poorer. As expected, the thicker films had higher physical properties compared with thinner ones. Although heat ageing may not affect XNBR films much, results indicated that XNBR films subjected to accelerated ageing showed higher tensile strength with lower elongation at break value than the unaged films. Crosslink density was estimated using the equilibrium swelling method. The role of ZnO is clear in XNBR film formation as the overall crosslink density of XNBR-ZnO film increased with increased amounts of ZnO. However, there is no clear relationship between the physical properties and the estimated crosslink density in this study.