| 摘要 |
The invention relates to a mat made of needle-punched strands comprising a strand made of mineral glass that has been sized by a composition comprising water, where the solids content of said composition comprises 1-30 wt % coupling agent and 30-99 wt % polyvinylpyrrolidone. The invention also relates to a method for the preparation of a mat comprising a) the deposition or projection of sized strands onto a moving belt to form a blanket of said strands, which is driven by said belt, then b) the needle punching with barbed needles which pass through said blanket and move in the direction of the blanket at substantially the same speed as the blanket when they pass through it, with a punch density ranging from 1 to 25 punches per cm2. This method is rapid and effective, and the mat obtained can be deformed easily by hand to be placed in a mold for the manufacture of a composite by the injection of resin (RTM), This mat can also be incorporated into a sheet of preimpregnated material (SMC) and be molded under pressure.
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