High performance short jute fibre preforms for thermoset composite applications

Jute fibre reinforced composites (JFRCs) are facing challenges to composite manufacturers due to the high cost of dry fibre preforming and inferior fibre performance compared to other commonly used natural plant fibres such as flax, sisal, hemp, and kenaf. Therefore, long fibre architecture jute fibre preforms often cannot fulfil the performance requirement of the composites. Using shorter length of jute fibres and then transform them into dry preforming sheet can ideally be used in manufacturing intricate composite products with low processing cost and high fibre reinforcing effect. On the other hand, short jute fibres suffer with extremely low fibre content and hence, they are difficult to use in making complex shape composite structures. In this work, a highly individualised and chemically treated (alkali) short jute fibre preforms with increased fibre contents were developed with the help of compression moulding. Composites were fabricated by impregnating the dry fibre preforms with epoxy resin by wet layup technique and cured in the hot press. These composites were found to have significantly higher mechanical properties when compared to traditional randomly orientated short jute fibre composites; showing the tensile strength similar to 93 MPa and flexural strength similar to 190 MPa for these composites, are the highest than any other natural short fibre composites reported so far in the literature. It was found that the extent of the improvement of mechanical properties of these composites, is related with the content of fibre in the composites, chemical modification of fibre ensuring higher bonding between the fibre and matrix. This work highlights new insights into high performance short jute fibres. If short jute fibres can be transformed into highly packed dry fibre preform, then it can be used in many semi-structural and structural composite applications.