Reinforcing-thermoplastic mat and method of forming such a mat
A method of forming a mixed fiber mat comprising forming a multi-layer mat from a first substantially planar structure of reinforcing fibers, such as a continuous strand fiberglass mat, and a first layer of thermoplastic fibers, such as polypropylene fibers. The multi-layer mat is subsequently needle-punched to intertwine the fibers. The mixed fiber mat preferably comprises a first continuous strand glass fiber mat and a first layer of thermoplastic fibers needle-punched together to intertwine the fibers. The mixed fiber mat can be heated to melt the thermoplastic fibers and then cooled to harden the thermoplastic to form a matrix. A composite is formed by this heating and cooling process. Other fibers can be substituted for the glass and polypropylene fibers.
1 . A method of forming a mixed fiber mat, the method comprising:
(a) forming a multi-layer mat from a first substantially planar structure of reinforcing fibers and a first layer of thermoplastic fibers; and
(b) needle-punching the multi-layer mat to intertwine the fibers.
2 . The method in accordance with claim 1 , wherein the thermoplastic fibers further comprise polypropylene fibers and the substantially planar structure of reinforcing fibers further comprises a continuous strand glass fiber mat.
3 . The method in accordance with claim 2 , wherein the step of forming the multi-layer mat further comprises disposing staple polypropylene fibers on a first side of the continuous strand glass fiber mat.
4 . The method in accordance with claim 3 , wherein the step of forming the multi-layer mat further comprises disposing staple polypropylene fibers on a second side of the continuous strand glass fiber mat.
5 . The method in accordance with claim 4 , further comprising the step of forming at least one additional layer.
6 . The method in accordance with claim 3 , wherein the step of forming the multi-layer mat further comprises disposing a second continuous strand glass fiber mat on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
7 . The method in accordance with claim 3 , wherein the step of forming the multi-layer mat further comprises disposing a second glass fiber mat on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
8 . The method in accordance with claim 3 , wherein the step of forming the multi-layer mat further comprises disposing a plurality of staple glass fibers on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
9 . The method in accordance with claim 2 , further comprising the steps of placing the multi-layer mat in a mold at sufficient pressure and temperature to melt the polypropylene fibers, and then cooling the multi-layer mat to a temperature sufficient to harden the melted polypropylene fibers.
10 . The method in accordance with claim 1 , wherein the thermoplastic fibers further comprise fibers selected from the group of acrylic-based fibers, nylon type fibers, polyester fibers, polyethylene fibers and bi-component fibers.
11 . The method in accordance with claim 1 , wherein the substantially planar structure of reinforcing fibers further comprises fibers selected from the group of type A glass fibers, type E glass fibers, type C glass fibers, type ECR glass fibers, type S glass fibers, carbon fibers, aramid type fibers and nylon fibers.
12 . The mixed fiber mat produced according to the method of claim 1 .
13 . A mixed fiber mat comprising a first substantially planar structure of reinforcing fibers and a first layer of thermoplastic fibers needle-punched together to intertwine the fibers.
14 . The mixed fiber mat in accordance with claim 13 , wherein the thermoplastic fibers are staple polypropylene fibers and the substantially planar structure of reinforcing fibers further comprises a continuous strand glass fiber mat.
15 . The mixed fiber mat in accordance with claim 14 , wherein the layer of staple polypropylene fibers are disposed on a first side of the continuous strand glass fiber mat.
16 . The mixed fiber mat in accordance with claim 15 , further comprising staple polypropylene fibers disposed on a second, opposite side of the continuous strand glass fiber mat.
17 . The mixed fiber mat in accordance with claim 16 , further comprising at least one additional fiber layer.
18 . The mixed fiber mat in accordance with claim 15 , further comprising a second continuous strand glass fiber mat disposed on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
19 . The mixed fiber mat in accordance with claim 15 , further comprising a second glass fiber mat disposed on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
20 . The mixed fiber mat in accordance with claim 15 , further comprising a plurality of staple glass fibers disposed on a side of the first layer of polypropylene fibers that is opposite the first continuous strand glass fiber mat.
21 . The method in accordance with claim 13 , wherein the thermoplastic fibers further comprise fibers selected from the group of acrylic-based fibers, nylon type fibers, polyester fibers, polyethylene fibers and bi-component fibers.
22 . The method in accordance with claim 13 , wherein the substantially planar structure of reinforcing fibers further comprises fibers selected from the group of type A glass fibers, type E glass fibers, type C glass fibers, type ECR glass fibers, type S glass fibers, carbon fibers, aramid type fibers and nylon fibers.