Development of biopolymer filled natural rubber latex-based composite films to enhance biodegradation

Abstract

Natural rubber latex (NRL) is the primary resource in developing thin film products including NRL gloves. These comprehensive applications of NRL are lead to the widespread formation of discarded solid material. Majority of these NRL-based product wastes are subjected to an incineration, landfill, or recycling. Recycling of NR waste is not usually effective owing to expensive and inadequate resources. Therefore the generation of heavy buildup of NR waste has become an immense social and environmental issue. Although NRL is biodegradable in nature, it has become more resistant to degradation, with the alteration of its properties to meet the processing requirements. To reduce the rising of NR waste problem, an attempt to enhance biodegradation process by coupling NR with degrading biomaterials has attracted more interest in research. Therefore this study is focused on evaluating applicability of corn-derivatives (cornstarch (CS), corn flour (CF), and corn grain (CG)) to develop a novel NRL-based biocomposite to enhance biodegradation as well as physico-mechanical, aging properties and compare with the conventional fillers. Corn-derivatives were employed to enhance the biodegradability and physico-mechanical properties of NRL-based composite films by changing filler content from 0 to 50 phr. Significant alteration in physico-mechanical properties were noticed with the type of the filler and NR-CG demonstrate improved adherence with NR matrix. Moreover addition of CG in NRL-based composite films increased degradation; with exceeding 70% mineralization detected for 50 phr CG loading after 15 weeks of soil burial. The agreement among physico-mechanical properties and biodegradation restrict the CG loading in the NRL-based composite films to 20 phr by obtaining the specifications of NRL-based products. The results showed that NRL-based composite films with CG loading of 20 phr support to the ASTM D3578, the specification for producing NRL gloves; with 50% mineralization after 15 weeks of soil burial. A glove material was successfully produced with NRL-based compounds including CG 20 phr loading and further improvements of composite films can be done by using it with industrial glove manufacturing process.