Spray deposition of cork reinforced polyester

Abstract

The objective of this research is to enable large part or high volume manufacturing processes to make consumer or industrial products from a cork reinforced polymer composite, similar to current applications of glass reinforced polyester. The low initial investment and high flexibility of the spray lay-up process make it an attractive candidate to study. A spray lay-up apparatus was successfully constructed and employed in manufacturing parts from a hybrid material composed of granulated cork, chopped glass strand, and a polyester matrix. The material was tested for tensile and flexural properties following relevant ASTM standards. The material was found to have a tensile strength of 4.4 MPa and tensile modulus of 850 MPa. The flexural strength and modulus were 9 MPa and 830 MPa, respectively. Adding a fiberglass skin to the cork hybrid significantly improved its flexural strength. Additionally, a small turbine blade prototype was created as a proof of concept. It is recommended that further work focus on optimizing the hybrid material's properties, re-designing and optimizing the apparatus used for the spray-up process, and demonstrating material viability by manufacturing a cross section of a large turbine blade.