Preparation And Properties Of Flame Retardant And Environmentally Friendly Jute/Poly (Butylene Succinate) Composites

With the increasing prominent energy crisis and environmental issues, the research of natural fiber reinforced biodegradable polymer composites has become a new hot spot. The jute fiber has advantages of easy availability, low price and excellent specific strength. Among the biodegradable polymer materials, polybutylene succinate(PBS) has the best overall performance. It has excellent mechanical properties, good heat resistance and easy processing. So jute reinforced PBS composites have excellent properties and belong to environmentally friendly materials. However, PBS and jute fibers both are flammable and there is a serious melt dripping during the combustion of PBS, which affect the application ranges of the composites. Therefore, by improving the flame retardancy of the composites, the applications can be expanded in automotive industry, electrical, electronic, aerospace and other fields.In order to improve the interface bonding between jute and PBS, the surface treatment like alkali, silane coupling agent KH-560 and homemade 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-based silane coupling agent (DOPO-KH-560) were used. The results showed that the KH-560 treated jute/PBS composite has the best mechanical properties, and the DOPO-KH-560 treated comes second. The limiting oxygen index (LOI) of DOPO-KH-560 treated jute/PBS composites has risen by 5%. All the treatments have reduced the crystallization temperature and initial decomposition temperature, but improved the char residue.By comparing the properties of DJ-PBS made from homemade DOPO-KH-560 treated jute and PBS, it is found that the optimum concentration of DOPO-KH-560 is 10% and the optimum treated time is 2h. Moreover, the optimum content of the modified jute fiber is 10%.DOPO has been chosen as flame retardant and added to DJ-PBS, which improved the flame retardancy of the composites.15% DOPO increased the LOI to 28.0% and the vertical burning test (UL-94) reached the level of V-0. But at the same time, it decreased the mechanical properties of the composites. The flexural strength, flexural modulus and the elongation at break respectively decreased 33.2%,31.8%,28.3% compared with DJ-PBS. The composite was environmentally friendly, but not combined good flame retardancy and mechanical properties, so its use value has reduced a lot.The flame retardant DDE compounded by DOPO and diatomaceous earth was used in DJ-PBS. The experimental results had shown that the composite has the best overall performance when the diatomaceous earth content of compounds is 10%.15% DDE increased the LOI to 31.9% and the vertical burning test (UL-94) reached the level of V-0. Meanwhile, the composite has good mechanical properties. The flexural strength, flexural modulus respectively decreased 12.0%,2.5% and the tensile strength increased 8.6% compared with DJ-PBS. DDE also improved the thermal stability and char residue of the composite. Thus, DDE flame retardant DJ-PBS composites combines excellent flame retardancy, good mechanical properties and environmentally friendly, it will be more widely used in various fields.