Abstract:
Quaternary boron salts are used as initiators of polymerisation in adhesive compositions for bonding low surface energy substrates such as polyolefins. The quaternary boron salts are of the formula I wherein R1 is C1-C10 alkyl, R2, R3 and R4, which may be the same or different, are, C1-C10 alkyl or C3-C10 cycloalkyl, phenyl, or phenyl-substituted C1-C10 alkyl or C3-C10 cycloalkyl, provided that any two of R1-R4 may optionally be part of a carbocyclic ring, and M+ is a metal ion or a quaternary ammonium ion. Particular examples of initiator compounds include sodium tetraethyl borate and lithium tetraethyl borate, lithium phenyl triethyl borate and tetraethylammonium phenyl triethyl borate.
Abstract:
Electron donor compounds, suitable for use as adhesives or as components in adhesives, contain a carbon to carbon double bond attached to an aromatic ring and conjugated with the unsaturation in the aromatic ring.
Abstract:
To provide a pressure-sensitive adhesive sheet that is free of swelling or deformation of a substrate due to migration of a liquid component from the pressure-sensitive adhesive layer and has acceptable processability, the pressure-sensitive adhesive sheet includes a carrier film; an elastomer film provided on one surface of the carrier film; and a pressure-sensitive adhesive layer provided on the elastomer film, in which the pressure-sensitive adhesive layer includes a composition that contains an acrylic polymer as a main component and a compatible component being compatible with the acrylic polymer and liquid or paste-like at room temperature, and in which the carrier film has a heat shrinkage of 3.0% or more and 4.5% or less in the longitudinal direction and 1.2% or more and 4.2% or less in the transverse direction.
Abstract:
Metal alkyl borohydrides are used as initiators of polymerisation, particularly in adhesive compositions for bonding a wide range of substrates including low surface energy substrates such as polyolefins. As described, the metal alkyl borohydrides are of the formula I or II. wherein R1 is C1-C10 alkyl, R2 and R3, which may be the same or different, are H, D, C1-C10 alkyl or C3-C10 cycloalkyl, phenyl, or phenyl-substituted C1-C10 alkyl or C3-C10 cycloalkyl, provided that any two of R1-R3 may optionally be part of a carbocyclic ring, and M+ is a metal ion. In particular, alkali metal trialkyl borohydrides are used, the alkali metal salt being selected from: Lithium triethylborohydride, Sodium triethylborohydride, Potassium triethylborohydride, Lithium tri-sec-butylborohydride, Sodium tri-sec-butylborohydride, Potassium tri-sec-butylborohydride, and Lithium triethylborodeuteride. Other exemplified compounds which are less effective on low surface energy substrates include Lithium 9-borabicyclo [3.3.1]-nonane (9BBN) hydride, Lithium thexylborohydride, Lithium trisiamylborohydride and Potassium trisiamylborohydride.
Abstract:
Aerobically hardening adhesives based on polymers of acrylates or methacrylates having a relatively high boiling point such as polyurethane (meth)acrylates are described, wherein the adhesives contain at least one initiator capable of forming free radicals, at least one accelerator, and at least one siccative. Such adhesives are largely odorless and harden completely such that the adhesive surface at the boundary with air is not tacky.
Abstract:
A composition of matter includes a polymerizable mixture comprising 1 to 99 weight percent of a first monomer and an initiator therefor, the first monomer being one of 1) at least one free-radically polymerizable monomer or 2) at least one cyanate ester monomer, and 99 to 1 weight percent of a second monomer and an initiator therefor, the second monomer being the member of 1) or 2) that is not selected as the first monomer, wherein the curative for the cyanate ester is a transition metal-containing organometallic compound curing agent and the curative for the free-radically polymerizable monomer is a free-radical generating curing agent or a transition metal-containing organometallic compound. The polymeric mixtures are useful, for example, in applications requiring high performance, such as high temperature performance; in composites, particularly structural composites; structural adhesives; vibration damping materials; electronic applications such as printed wiring boards, semiconductor encapsulants and electronic adhesives; photoresists; injection molding and prepregs; protective coatings; tough self-supporting films; and high performance binders. In addition, a curable composition including (1) an ethylenically unsaturated monomer or (2) an ethylenically unsaturated monomer and a cyanate ester monomer, and certain organometallic neutral compounds is useful in the graphic arts.
Abstract:
The invention concerns a reagent kit designed to produce elements of synthetic resin for anchoring fixation elements in place by bonding them in multi-cavity plugs. The reagent kit comprises (a) a reagent mixture containing 2,2-bis-[4-(methacryloxyethoxy)phenyl]propane and an optionally unsaturated polyester resin, vinyl resin or acrylic resin or a mixture of these, (b) an accelerator component comprises an organic peroxide and (c) a filler component, the accelerator component (b) being kept separate from the reagent mixture (a) before use.
Abstract:
A thermally curable adhesive composition that includes a fluxing agent that also acts as an adhesive is provided. The composition includes: (a) a fluxing agent represented by the formula RCOOH, wherein R comprises a moiety having two or more carbon-carbon double bonds wherein in one embodiment, at least one is within an acrylate or methacrylate group, and which may further contain at least one aromatic moiety; (b) a carboxylic acid neutralizing agent; (c) optionally, a crosslinkable diluent; (d) optionally, a source of free radical initiators; and (e) optionally, a resin. The composition can be applied directly onto the surface(s) of devices that are to be joined electrically and mechanically. These devices include, printed circuit substrates, connectors, components, cables, and other electrical devices having metallization patterns to be soldered together by means of a solder-bumped pattern on one or both surfaces. Alternatively, a solder paste, comprising solder powder mixed with the fluxing agent of the present invention can be used. During the reflow step, the fluxing agent promotes wetting of the solder to the metallization patterns and, simultaneously, the fluxing agent itself crosslinks to mechanically bond and encapsulate the surfaces and their metallizations. The compositions can also be used to formulate sinterable conductive ink.
Abstract:
Water resistant, low haze acrylic emulsion pressure sensitive adhesive compositions for use in decorative, light management or optical articles are disclosed. These emulsion pressure sensitive adhesives comprise (a) 50-90% by weight n-butyl acrylate, and (b) 10-50% by weight 2-hydroxy ethyl acrylate, or 2-hydroxy ethyl methacrylate, hydroxy propyl acrylate monomer, or mixtures thereof. These emulsion pressure sensitive adhesives can be used in wet lamination processes, and exhibit less than 2% increase in haze, less than 2% increase in opacity and greater than 95% transmittance after the wet lamination process.