1. 1. A PP-film and a special sized glass fibre, which satisfy the requirements for PP Split-Warpknit textile structures, have been developed;
2. 2. A PETP film and a compatible glass fibre, which satisfy the requirements for PETP Split-Warpknit textile structures, have been selected;
3. 3. An Aramide/PEI weft insertion warp knitted textile structure has been developed;
4. 4. The techniques for splitting, stretching and producing warp beams have been developed, based on the "bobbins" technology;
5. 5. Existing knitting equipment and knitting technologies have been adapted to produce uni-axial and bi-axial Split-Warpknits in an efficient and economical way. Multi-axial Split-Warpknits are under development;
6. 6. The cost-efficiency of the Split-Warpknits can be increased considerably for long running structures by using the FSSB- or ISO-system;
7. 7. Preferably, the Split-Warpknits should be pre-consolidated to be used in the standard GMT-process;
8. 8. The industrial feasibility of the QUIKTEMP process has been proven on a demonstrator part (Upper Washer Spring Seat);
9. 9. The vibrational technique can improve processing, but seems to be beneficial only in special cases with suitable geometry and tool design;
10. 10. With the Split-Warpknits mechanical properties comparable to Twintex can be achieved, at lower cost;
11. 11. Different industrial demonstrator parts have been produced.
The findings and results obtained during the entire research and development period are a valuable basis for further, specific development tailored to certain applications, within the sector of long-fibre reinforced thermoplastic textile structures.
The industrial objectives of this research programme is the development of a thermoplastic preimpregnated textile structure, based on the split-film technology and the knitting technique, and the development of adequate processing techniques for mass production application (cycle time less than 2 minutes) and for high-end applications.
This research programme will result in a new class of composite materials which will be cost-effective to Woven Thermoplastic Fabrics, and which will have a higher performance/weight ratios than GMT, SMC, and similar materials.
To develop the split-film co-knitted thermoplastic composites, the following major research tasks have to be completed :
a. selection of material and development of a good coupling between fibre and matrix;
b. the transformation of the raw material to a thermoplastic pre impregnated structure;
c. development of a cost-effective processing technique, based on a good matrix-forming (wettability, fibre-polymer coupling), for short cycle time process-mass production and for high-performance moulding.
d. design and fabrication of test-products for both production methods.
Performance/weight ratio in the order of 5 to 7 times the ratio of GMT and considerable cost-saving compared to existing woven fabrics (about 25%) are forecast.
The economical opportunities are :
- mass production : automotive industry;
- high-end applications : machine equipment, sport and leisure, communication and aerospace.
Funding SchemeCSC - Cost-sharing contracts
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