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ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Plant Polymer Research » Research » Publications at this Location » Publication #361713

Research Project: Conversion of Polysaccharides and Other Bio-based Materials to High-Value, Commercial Products

Location: Plant Polymer Research

Title: Mechanical characterization and effect of water absorption on PLA/carbon fiber composites in injection molding

item Lingam, M - Bradley University
item Guo, Gangjian - Bradley University
item Yoo, Jung-woon - Bradley University
item Finkenstadt, Victoria

Submitted to: Society of Plastics Engineers Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/6/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary: A biobased polymer was loaded with carbon fibers to increase toughness and tensile strength. Biobased polymers are generally weaker than petroleum-based plastics. A critical weight limit was determined above which there is no added benefit in mechanical properties; therefore, the cost of the composite will be less. Because the biobased polymer is sometimes susceptible to moisture, water absorption was determined including its effect on mechanical properties. Carbon fiber reinforced biobased composites can be used to replace existing petroleum-based composites on a cost-competitive basis, resulting in better environmental outcomes.

Technical Abstract: This study investigated the mechanical behaviors of injection molded polylactic acid (PLA) composites reinforced with carbon fiber (CF) at different fiber loading levels (5 wt%, 10 wt%, 15 wt% and 20 wt%). PLA, a biodegradable thermoplastic derived from renewable resources, has been replacing petroleum-based plastics in many applications due to its sustainability and low environmental impact. However, the low mechanical strength limits its wide structural applications. The addition of a small amount of CF significantly increased the tensile strength and modulus while leading to reduced ductility. Compared to pure PLA, the composites with 5 wt% CF content had a 40% increase of tensile modulus and a 63% decrease of elongation-at-break. The effects of water absorption on the mechanical properties of PLA/CF composites were also studied.