Use of a low binder fiber mat with a support mat for fabricating a fiber reinforced polymeric foam composite
A process for preparing a fiber reinforced polymeric foam composite includes introducing a foamable mixture into a low binder expandable fiber mat and then expanding the foamable mixture into a polymeric foam between top and bottom facing sheets such that the fibers of the low binder fiber mat become dispersed within the polymeric foam, wherein the low binder fiber mat is part of a composite web that further comprises a support web. Such a composite web is particularly useful for preparing reinforced polymeric foam composites that contain a fiber reinforced polymeric foam having a thickness of greater than two inches (5.08 centimeters) and fibers substantially distributed therein.
1. A process for fabricating a fiber reinforced polymeric foam composite comprising the steps:
a) conveying a length of bottom facing sheet;
b) conveying above the bottom facing sheet a first expandable fiber mat;
c) conveying above the expandable fiber mat a composite web from a roll; the composite web comprising a low binder fiber mat and a support mat and oriented such that the support mat is below the low binder fiber mat;
d) conveying a length of top facing sheet above the composite web;
e) dispensing a foamable mixture between at least one of:
(i) the bottom facing sheet and first expandable mat, if dispensing occurs prior to step (b);
(ii) the first expandable fiber mat and support mat of the composite web, if dispensing occurs after step (b); and prior to step (c); and
(iii) the composite web's low binder fiber mat and top sheet, if dispensing occurs after step (c);
f) constricting the bottom and top facing sheet through a metering gap, achieving penetration of the foamable mixture into the expandable fiber mat and low binder fiber mat; and
g) expanding the foamable mixture into a polymeric foam.
2. The process of claim 1 , wherein the first expandable fiber mat is part of a second composite web.
3. The process of claim 1 , wherein the bottom facing sheet is part of a second composite web that contains the first expandable fiber mat and wherein steps (a) and (b) are accomplished simultaneously by conveying the composite web containing the bottom facing sheet and first expandable fiber mat.