Thermoplastic resin compositions suitable for use in transparent laminates
View Patent ↗The present invention is an improved polymeric resin composition comprising or consisting essentially of from about 70 wt % to about 79 wt % units derived from ethylene and from about 21 wt % to about 30 wt % units derived from an α, β-unsaturated carboxylic acid having from 3 to 8 carbons. Resins of the present invention are particularly suitable for preparing transparent laminates useful as glazing elements that provide a greater measure of safety than non-laminated glazing elements. Laminates of the present invention have 3% haze or less without the addition of amines.
1. A laminate article comprising at least one transparent interlayer, wherein the transparent interlayer is obtained from a resin composition consisting essentially of copolymerized units of ethylene and from 20 to 23 wt % of copolymerized units of a carboxylic acid monomer selected from acrylic acid or methacrylic acid, wherein 20% to 35% of the acid groups are neutralized; and the resin has a melt index of about 60 g/10 min or less prior to neutralization, and wherein the laminate article has a haze of 3% or less after heating to a temperature of at least 120° C. and cooling to 40° C. at a rate of less than 1° C./min; and further wherein the peel strength of the laminate article is from 16 to 47 lbs/inch when measured at an angle of 90° at a peel rate of 1 inch/min, provided that the transparent interlayer is an extruded sheet having a moisture level of 0.066 wt % or less; and further wherein said transparent interlayer has an adhesion to glass of at least 200 J/m 2 , when measured by Double-Cantilever Beam testing; and said transparent interlayer has an impact toughness of at least 300 J/m 2 , when measured according to ASTM 1822.
2. The laminate article of claim 1 , wherein the resin has a melt index of about 55 g/10 min or less prior to neutralization.
3. The laminate article of claim 1 , wherein the resin has a melt index of about 50 g/10 min or less prior to neutralization.
4. The laminate article of claim 1 , wherein the resin has a melt index of about 35 g/10 min or less prior to neutralization.
5. The laminate article of claim 1 , wherein the resin has a melt index of about 2.5 g/10 min or less after neutralization.
6. The laminate article of claim 1 , wherein the resin has a melt index of about 1.5 g/10 min or less after neutralization.
7. The laminate article of claim 1 , wherein the transparent interlayer has a thickness of from about 0.38 to about 2.60 mm.
8. The laminate article of claim 1 , further comprising at least one additional layer selected from the group consisting of ionomeric interlayers having from 15 to 20 wt % acid before neutralization; EVA copolymer interlayers; polyurethane interlayers; polyvinyl chloride polymer interlayers; PVB interlayers; adhesive layers; and rigid structural layers.
9. The laminate article of claim 8 , comprising a rigid structural layer that is a layer of glass.
10. An application comprising the laminate article of claim 1 , said application selected from the group consisting of windows; windshields; sidelites; structural support units; and other architectural units.
11. The application of claim 10 , wherein a building comprises the window; an automobile, a plane, or a train comprises the windshield or the sidelite; stairs, a floor, a wall, or a partition comprises the structural support unit; or a ceiling comprises the other architectural unit.