MULTILAYER ARTICLES AND METHODS FOR MAKING MULTILAYER ARTICLES
In one embodiment, a sheet, comprises: a cap layer comprising an acrylic polymer; and a base layer, where the cap layer and the base layer were co-extruded to form the sheet, which is thermoformable. The base layer comprises a polycarbonate. The cap layer is 10% to 30% of an overall thickness and the overall thickness is 5 mil to 500 mil.
1 . A sheet, comprising:
a cap layer comprising an acrylic polymer, wherein the cap layer is 10% to 30% of an overall thickness and the overall thickness is 5 mil to 500 mil; and
a base layer comprising a polycarbonate;
wherein the cap layer and the base layer were co-extruded to form the sheet, which is thermoformable.
2 . The sheet of claim 1 , wherein the sheet has a pencil hardness greater than or equal to HB.
3 . The sheet of claim 1 , wherein the sheet has a pencil hardness greater than or equal to H.
4 . The sheet of claim 1 , wherein the base layer comprises a copolycarbonate.
5 . The sheet of claim 2 , wherein the base layer comprises a cycloaliphatic polyester copolymer and a polycarbonate, wherein the cycloaliphatic polyester copolymer is poly(1,4-cyclohexylene dimethylene co-ethylene terephthalate).
6 . The sheet of claim 1 , wherein the cap layer is on and in contact with the base layer.
7 . The sheet of claim 1 , wherein the overall thickness is 5 mil to 40 mil.
8 . The sheet of claim 1 , wherein the sheet is thermoformed at a temperature below the glass transition temperatures of the acrylic polymer and the polycarbonate.
9 . The sheet of claim 5 wherein the blend comprises 20 wt % to 50 wt % cycloaliphatic polyester, balance polycarbonate.
10 . The sheet of claim 1 , wherein the acrylic polymer comprises an alkyl(meth)acrylate.
11 . The sheet of claim 10 , wherein the alkyl(meth)acrylate comprises a poly(methyl)methacrylate.
12 . The sheet of claim 11 , wherein the poly(methyl)methacrylate has a haze value of less than or equal 5% as determined according to ASTM D1003-00.
13 . A sheet, comprising:
a cap layer comprising an acrylic polymer, wherein the cap layer is 10% to 30% of an overall thickness and the overall thickness is 5 mil to 500 mil; and
a base layer comprising a cycloaliphatic polyester copolymer and a polycarbonate, wherein the cycloaliphatic polyester copolymer is poly(1,4-cyclohexylene dimethylene co-ethylene terephthalate);
wherein the cap layer and base layer were co-extruded to form the sheet which is thermoformable; and
wherein the sheet has a pencil hardness greater than or equal to HB.
14 . The sheet of claim 13 , wherein the acrylic polymer comprises an alkyl(meth)acrylate.
15 . The sheet of claim 14 , wherein the acrylic polymer comprises poly(methyl)methacrylate.
16 . A method for making an article, comprising:
melting an acrylic polymer in an extruder;
forming a molten mixture comprising a polycarbonate in an extruder;
co-extruding the acrylic polymer and the molten mixture to form a sheet which is thermoformable, wherein the molten mixture forms a base layer and the acrylic polymer forms a cap layer on the base layer;
wherein the cap layer is 10% to 30% of an overall sheet thickness; and
wherein the sheet has a pencil hardness greater than or equal to HB.
17 . The method of claim 16 , further comprising thermoforming the sheet at a temperature below the glass transition temperatures of the acrylic polymer and the polycarbonate.
18 . The method of claim 16 , wherein the acrylic polymer comprises an alkyl(meth)acrylate.
19 . The method of claim 16 , wherein the overall sheet thickness is 3 mil to 20 mil.
20 . The method of claim 16 , wherein the cap layer is co-extruded on and in contact with the base layer.