In this research study, the degradation of natural rubber was applied for applications in agriculture products such as rubber mulch. This work included the synthesis of 20% wt silica/ natural rubber composites from high ammonia concentrate latex (HA) and fresh latex (FL). They were casted by film casting. The experimental study of rubber composite degradation was done by putting the samples underground and above the soil surface under accelerated degradation test box equipped with a solar simulator lamp for a period of 50 days. Samples were characterized by scanning electron microscopy (SEM) to examine the dispersion on cross-sectional area between natural rubber and silica. Thermogravimetric analysis (TGA) was used to analyze the thermal stability of the composites. Tensile strength (MPa), modulus at 100% elongation (MPa), and elongation at break (%) of the samples after aging were tested by focusing on. It was found that thermal degradation of natural rubber compounds consisted of one step of mass loss between 341°C and 455°C. The SEM result showed good dispersion of Si in the rubber samples. Moreover, it was found that before aging, the composite samples had higher tensile strength than that of the rubber. After aging, the composite samples had lower tensile strength than that of the rubber. Elongation @ break value of HA/Si and FL/Si after aging were decreased obviously.

Degradable materials from 20wt% chitosan loading and natural rubber (CS/NR) were prepared by solution casting without surface treatment to study their thermal and mechanical properties after degradation test in aging condition. The test was done in an acrylic degradation box with 600 W light and high humidity for accelerate degradation condition. Samples included high ammonia concentrated latex (HA) with no filler, fresh latex (FL) with no filler, HA with chitosan filler, FL with chitosan filler, and natural rubber with shrimp shell filler to compare the result with chitosan filler. After degradation test, thermal properties from TGA both before and after degradation showed that the fillers effected on these composite materials. TGA result of CS/NR composite with aging at temperature 100 °C for 10 h and 20 h showed that chitosan slightly effected on thermal stability of composites when compare to natural rubber. SEM images were compared before and after degradation of HA and FL with no filler, chitosan filler, and shrimp shell. It was clearly seen that the samples degraded as the shape and size were changed. Tensile testing values showed that longer aging time could lead to the degradation in CS/HA and lower the tensile strength.