การเตรียมและสมบัติทางกายภาพของสารปรับปรุงดินที่เตรียมจากน้ำยางธรรมชาติ

Abstract

In this research, a new biopolymer composite was studied and explicated. The improvement of soil structure and aggregate strengthening of sandy loam soil using natural rubber (NR) was studied. The research can be divided into 2 parts. For the first part, The formation of biopolymer composites form soil and NR latex treated with 2 and 6 wt% of Tween 80 was investigated, respectively. The NR latex solution is used different condition (3, 5 and 7 wt% of dry mass soil) to improved on soil mechanical properties of at different cured times and treatment conditions. The second part, The biopolymer composite formed soil and non-treated NR latex, was studied. NR latex is a biopolymer with the potential as soil strengthening materials due to the cross-link of hydrocarbon polymer compounds. The curing time and treatment conditions of composite were observed. The results showed that the NR latex with 2 wt% Tween 80 was well distributed in the soil and improved aggregate strengthening of composite due to potential interparticle interlocking of structure composite. The compressive strength and direct shear strength of the final treated composite were studied under various curing conditions. As a result of curing time and moisture content affected to mechanical properties, the composite treated with NR latex cured for 7 days showed the highest bond strength in thermal dry condition compared to those cured in air dry and submerged air dry conditions. The results showed that the moisture content is important due to the continuous evaporation of water which leads to the increase of composite strength. However, curing composite at thermal condition ( 45+5 'C) overtime leads to shrinkage and becoming brittle. Additionally, The composite cured in both conditions of air dry and submerged air dry showed an efficient bond strength compared to that cured in thermal dry, which over cured time. The soil treated with NR latex 5 wt% showed the highest strength on final day at 42 days cured both of air dry and submerged air dry conditions. The mechanical strength of the composites depends on quantities of NR latex, interoperation of NR latex has increase to bond strength of the composite lead to improved mechanical properties. However, the biopolymer composite treated with NR latex 7 wt% showed that the agglomerate of NR lead to inefficient to potential interparticle of composite. Thus, the linkage and interaction between NR latex and soil particles appeared to depend on curing time, moisture content, NR content and curing conditions of biopolymer composites.