FR2500360A1 - - Google Patents

Abstract

WE WOVEN THICKNESS OF FABRICS IN NON-FUSIBLE FIBERS (CARBON, ARAMID, GLASS) IN CONJUNCTION WITH THERMOPLASTIC FIBERS (POLYOLEFIN, POLYESTER, POLYAMIDE, ETC), WE STACK SEVERAL THESE THICKNESSES AND THE HEATERS UNDER PRESSURE FIBERS NON FUSES ARE LINKED TO MELTED THERMOPLASTIC FIBERS.

Description

1. The present invention relates to a

  improved process for the production of laminates

  and the laminates thus produced, more particularly

  specifically for the production of thermoplastic laminates

  ticks reinforced with woven fabrics, either in the form of flat panels or curved pieces. According to the invention, the method consists in weaving thicknesses of fabrics from carbon fibers, aramid or

  glass together with polyolefin fibers

  fine, polyester, polyamide, polyether-

  sulfone or polyether-ether-ketone or others

  thermoplastic fibers, to assemble a plura-

  a layer of thicknesses to form a laminate, to heat the laminate under pressure to produce a moldable laminate, the number of thicknesses of fabric used being dependent on the requirements of

  performance for end use, the fi-

  thermoplastic berries used to bond the thicknesses together and to improve the properties

mechanical and other laminate.

  The invention will be described with reference to

  rant to the accompanying drawings: FIG. 1 shows an armor having 75% of a chain made of thermoplastic fibers as

  polythene on one side, and 25% on the oppo-

  sé, using aramid wefts b.

  Figure 2 shows an armor in which

  thermoplastic warp fibers are available

  tributed equally on both sides with

the weft aramid wire.

  Figure 3 shows a unidirectional fabric with

  thermoplastic warp and working yarn

aramid me.

  2. Figure 4 shows a satin weave allowing

  greater permeability than plain weave.

  An aramid fabric commonly used for reinforcing plastics is a plain weave fabric with 67 threads per 100 mm in both the warp and

  of the weft, consisting of aramid fiber 158 tex.

  For the production of a 25 mm thick laminate consisting of 15% by weight of polythene and 85% by weight of aramid fiber, the procedure is as follows:

  Question of economy, it should be

  to produce polythene as a chain, wire to wire, with aramid fiber. The linear density of the polythene chain is therefore 30% of that of aramid since the weights of aramid in the chain

  and the weft b of the base fabric are equal. A fi-

  this kind is a polythene monofilament

  0.25mm high density and it can be intro

  duit in the fabric, although there are many

  possible variations in weaving.

  To produce a laminate with a thickness of 25 mm from the fabric of FIG. 2, 85 thicknesses are placed on top of each other and they are put in a press with pressing plates heated to 1500C, or to a temperature

  superior when dealing with another material

  laugh. When the polythene has melted, a pres-

  about 1 MPa (150 psi or 10.5 kg / cm2) will consolidate the laminate to -25 mm thick, or bumpers 25 mm apart can be used in the press. After pressing the laminate

  is cooled, inside or outside the press.

  Choice of fiber and thermoplastic matrix and pressing conditions

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  3.depends on the end use for which the laminate is intended, as does the ratio of fiber to

the matrix.

  Carbon, aramid or glass fibers have a high resistance and a high modulus. Similarly the matrices are

  polyolefins, polyesters, polyamides, polyether-

  sulfone and polyether-ether-ketone.

  However, other fi

berries and dies.

  Laminates as described can be made by interlinking the fabric

  woven and the thermoplastic matrix under the

  film or particle and by heating with

  the assembly under pressure. The disadvantaged

  tages of this method are that thermoplastic films or particles are difficult to handle and that they can be difficult to manufacture. In laminates where a discontinuous layer of thermoplastic material is

  desirable, the manufacture becomes very complex.

  However, the thermoplastic materials in question are readily available under the

form of textile fibers.

  The present invention describes weaving

  a simple fabric that has both the fi-

  reinforcement bre and the thermoplastic matrix

in fibrous form.

  In the design of such a fabric, it

  there is a multitude of basic fabrics which can-

  may be selected in accordance with the intended end application. The choice of reinforcement fabric is made according to mechanical, thermal, chemical, electrical resistance

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  4. and other such properties requested in the final product. Similar considerations come into play in the selection of the type, quantity and distribution of the thermoplastic fiber. When these parameters have been established, the two are put together to provide

  a fabric which is mainly composed of

  su reinforcement and additional wires consisting of the matrix material under the

filamentary form.

  These additional threads can be warp or weft threads, or both. The layers of single fabric are then heated under pressure to melt the thermoplastic filaments, which, upon cooling, will bind together the layers of reinforcing fabric. It is also possible to produce

  a fabric in which the chain consists entirely-

  reinforcing fibers and the weft

  made entirely of thermoplastic fibers or vice

  vice versa. The thicknesses of such a fabric, when layered on top of each other in the same orientation, will produce a unidirectional laminate which has all of the reinforcing fibers in one direction only. A

  such fabric can also be used in la-

  multidirectional mined by orienting the fibers

  reinforcers as needed during the pre-

  laminate trim. The advantage of these thicknesses

  is that it is possible to manufacture

  mined without creping in the reinforcing fibers

  is lying. Another advantage is that the production

  curved laminate is facilitated.

  5. Simple bends can be made by molding them from a flat laminate before the

  thermoplastic material solidifies. Courts

  more complex bures can be made by selecting a thickness of fabric such as satin (Figure 4) capable of draping around

  of a curved mold before pressing.

  Another claimed advantage is that

  laminates with a high fiber content reinforce

  are produced easily and economically-

  lying and that it is possible by use

  of normal textile machine to melt the fi-

  thermoplastic laments partially or com-

  quite. This has the effect that the thermal material

  moplastic is not only woven with the reinforcing fabric, but also

related to it.

  This can be an advantage in the preparation of the laminate piled up before molding, in that it reduces the risk of fraying of the reinforcement fabric during the operation.

  of shaping. Likewise, if we use

  cutting methods using ultra-

  sounds or laser, which produce heat

  their, thermoplastic threads that are cut tend to melt and re-seal

edges.

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Claims (1)

- REVENDTCATTON -   Process for the production of woven laminates comprising weaving layers of fabric t l i l dte's ava C; l} bonïe; 1 il'lid O'il of glass, together with fibers of polyolefin, polyester, polyamide, polyether sulfone and   polyether-ethler-ketone or other thermo fibers   plastics, the assembly of a plurality of thick   sisters to form a laminate, heating the laminate under pressure to produce a moldable laminate, the number of thicknesses of fabric used being a function of performance requirements   in the end use, the fibers thermo-   plastics used to bond the thicknesses together and to improve the mechanical properties and others of the laminate.