The Research Of Resistance Aging Performance Of The PLA/Jute Multi-layer Composite Materials

With the development of science and technology, more and more new materials have been applied to the production life, the PLA/jute composite materials is one of them. Because of their excellent physical and mechanical properties and biodegradability talent showing itself in new composite materials, so it’s under a lot of attention. This topic choose the PLA/jute blending fiber needle thorn flocculus whose mix ratio is 30/70 as base material, by using pure mixed fiber flocculus layer and mix with pure PLA fiber flocculus interval layer adjusting proportion of the three kinds of different proportion of PLA/jute composite materials. Among which, the composite materials that the PLA content is 30% using pure mixed fiber flocculus layer method,the PLA content is 40%, 50% of the composite materials using mixed with pure PLA fiber flocculus interval layer to adjust proportion method, then using the hot pressing process, preparation of multi-layer mixed fiber composite material, then we studied its preparation technology, mechanical properties and aging properties. The main research content is as follows:1. Preparation and process optimization of PLA/Jute multi-layer blended fiber composite materialChoosing mold temperature and spread to the Angle as the factor of process parameters, by using the means of quadratic general rotary unitized design, to prepare different proportions of multi-layer mixed fiber composite materials and investigate the effect of the technological parameter to the bending strength and tensile strength,establishing regression equation, optimizing the process parameters, and get the PLA/jute flocculus that is suppressed by pure mixed fiber flocculus layer method of30/70, the optimum parameters of hot pressing temperature and the Angle of layer is:temperature of 206 ℃, spread to the angle of 45 °; for the composite material that the ratio was 40/60, 50/50, the regression equation was not significant.2. The study on mechanical properties of PLA/Jute multi-layer blended fiber composite materialAccording to the ratio the best technology of PLA/jute composite materials of30/70 to prepare the ratio of three kinds of multi-layer composite materials respectively, studies the rapid impact, quasi static impact and the bending resistance.The results show that the mechanical properties are 30/70>40/60>50/50. Compared with morphology analysis: using pure mix of PLA fiber flocculus layer legal content for 30% of the inter layer bonding of composites is firm, uniform internal structure,mechanical performance is good; to mix with pure PLA fiber flocculus interval layer regulation legal system of the PLA content is 40%, 50% of the composite material layer between the obvious stratification, bonding effect is poor.3. The resistance aging performance research of the composites after damp and heat treatmentThe PLA/jute composite materials are in the environment that the temperature is80 ℃, relative humidity is 80% and have a treatment of different time to study the aging performance, results show that with the increase of processing time, the mechanical properties decreased significantly, and a rapid drop in the treatment of 48 hours, more than 48 hours after conforms to the linear slow decline; microscopic observation of PLA and jute visible cracking phenomena appear in the bonding interface; from the IR and TG analysis, the peak of carbonyl has increased,degradation phenomenon appeared, and the initial decomposition temperature decrease after processing but higher than single material thermal stability.4. The resistance aging performance research of the composites after UV treatmentThe PLA/jute composite materials are handling different time under the UV light intensity of 300 w to study the aging performance, results show that with the increase of processing time, the mechanical properties decreased significantly, and conforms to the linear downward trend; microscopic observation of PLA and jute visible cracking phenomena appear in the bonding interface; from the IR and TG analysis, the peak ofcarbonyl has increased, degradation phenomenon appeared, but the thermal decomposition temperature nearly remains unchanged.