Composite gage and drain hole sealer

A composite preformed thermoplastic patch for sealing aperture in a workpiece comprising two components, an ionomer component and an olefinic/elastomeric component:

• a. the ionomer component comprising a melt blend of:
• i. an ionomeric copolymer of ethylene and an .alpha.,.beta.-ethylenically-unsaturated C.sub.3 -C.sub.8 carboxylic acid partially neutralized with a metallic cation;
• ii. 0 to 25 parts by weight (based on 100 parts ionomeric copolymer) of a non-ionomeric copolymer of the form E/X.sub.ii /Y.sub.ii where E is ethylene;
• X.sub.ii is one or more monomers selected from alkyl acrylate, alkyl methacrylate, vinyl acetate and alkyl monoesters of dicarboxylic acid wherein the alkyl groups have from 1-12 carbon atoms;
• and Y.sub.ii is one or more monomers selected from .alpha.,.beta.-ethylenically-unsaturated C.sub.3 -C.sub.8 carboxylic acids;
• wherein X.sub.ii is 0 to 60 weight percent and Y.sub.ii is 0 to 35 weight percent of the E/X.sub.ii /Y.sub.ii copolymer provided that X.sub.ii must be present if Y.sub.ii is not and Y.sub.ii must be present if X.sub.ii is not;
• iii. 1 to 10 parts by weight (based on 100 parts ionomeric copolymer) of a metallic coagent selected from the group consisting of metallic salts of acrylic acid and metallic salts of methacrylic acid;
• and
• iv. 0.2 to 15 parts by weight (based on 100 parts ionomeric copolymer) of filler;
• and
• b. the olefinic/elastomeric component comprising:
• i. 25 to 90 weight percent of an uncrosslinked elastomer, an olefinic polymer or a blend of an uncrosslinked elastomer and an olefinic polymer;
• ii. 1 to 10 weight percent multifunctional acrylic monomer;
• and
• iii. 0.1 to 5 weight percent of a free-radical curing agent;
• wherein the ionomer-based component (a) and the olefinic/elastomeric component (b) are intimately contacted under conditions sufficient to bond the components as layers into a unitary multi-layer structure to insure intimate, positive contact between the layers so that the structure retains its unitary form during storage and is installable as an integral preformed patch in a single application over the aperture in the workpiece but are contacted under conditions that are insufficient to cause free radical polymerization at the interface between the layers.