Textile production

4.3.5. Advances in textile composites
Perhaps in no other textile application has the importance of R&D by academic researchers worldwide been so significant as in the development of textile composites. Significant developments have taken place in fibres, matrix polymers and composites manufacturing techniques. The textile- manufacturing processes are less complex than injection moulding and laminating and they have the advantage of greater control of fibre placement and in ease of handling preforms. These textile structures may be planar two-dimensional (2D) fabrics – for example, knitted or nonwoven materials – or 3D woven, braided, nonwoven or knitted fabrics. Making use of the unique combination of lightweight, flexibility, strength and toughness, textile structures are now being increasingly recognized as an attractive reinforcement form for many composite applications.
As a route to mass production of textile composites, the production speed, material handling, material design flexibility and cost efficiency are some of the major factors determining the suitability of a textile reinforcement production process such as weaving, warp knitting, braiding or nonwoven technology for a given end-use application. The use of thermoset matrices is widespread at present. The resin is applied to the textile preform at the consolidation stage. Polyesters or epoxy matrices are applied by resin transfer moulding (RTM) process. Faster cure is possible with other resin formulation, mainly polyurethanes, suitable for reaction injection moulding (RIM) process. From the manufacturing point of view, however, the rational composite production process should be based on thermoplastic matrices which can be incorporated in a textile structure by the textile industry.
The advantages of textile techniques over the other techniques include homogeneity of matrix and reinforcing fibres, high drapability and a solvent- free process. The production of prepregs made from reinforcing fibres and thermoplastic matrix fibres opens up a new field of technical application by new types of semi-finished materials produced by the textile industry. More scientific work still needs to be done in order to understand the mechanisms involved in matrix-flow and fibre-matrix compatibility affecting bond strength. This knowledge is of great importance for the optimization of processing times for composites, which remains a determining factor for the market growth of composites.