KR20120046158A - Latent hardener for epoxy compositions - Google Patents

Abstract

Described herein are curing agents for epoxy resins consisting of the reaction products of amines, epoxy resins and elastomeric epoxy adducts. Further described are methods comprising shaking a solution of an amine, an epoxy resin and an elastomeric epoxy adduct as a dispersant in an organic medium at elevated temperature.

Description

Latent hardener for epoxy compositions

Partial continuation of the related application

US Provisional Application No. 61 / 186,547, filed June 12, 2009; US Application No. 12 / 497,040, filed July 2, 2009; US Provisional Application No. 61 / 313,199, filed March 12, 2010; And U.S. Application No. 12 / 762,892, filed April 19, 2010.

Field of invention

The present invention relates to latent hardeners for epoxy resins and, more particularly, to latent hardeners composed of a core material encapsulated or coated with a shell material.

Epoxy adhesives have been known for over 50 years and were one of the first high temperature adhesives to be commercialized. Once cured, the material maintains its adhesion over a wide range of temperatures, has high shear strength, and is resistant to weathering, oils, solvents, and moisture. Adhesives are commercially available as one-part adhesives or two-part adhesives and are available in several forms, for example as pastes, solvent solutions and support films. Among the three forms, one-part adhesive films generally provide excellent adhesive strength with better thickness uniformity, and have found practical use in the development of anisotropic conductive films, most notably flat panel displays for electronics.

To build a one-component adhesive film, latent hardeners, multifunctional epoxy resins, phenoxy resins, additives and optionally fillers are typically blended in one step. This composition is then cast as a film on the release layer. During the bonding process, the adhesive was transferred to one specific surface and the release layer was removed. Another surface is in contact with the film and the adhesive is cured with a strong thermoset adhesive by applying heat and / or pressure. In this example, the two components of the adhesive that can cause the material to cure with a thermoset adhesive are a hardener and a multifunctional epoxy. It is the latter to undertake the crosslinked network, but it is the former that causes it. During the curing process, the latent hardener first forms the ring opening adduct with the oxirane of the epoxy resin to initiate the polymerization of the multifunctional epoxy. Once produced, the additive product causes a cascade of ring-opening species to spread through the adhesive, resulting in a crosslinked thermoset material.

Hardener's active component generally consists of the reaction product of an amine compound (eg imidazole) with an epoxy resin. Such adducts are known to initiate and accelerate the curing of epoxy resins (Heise, MS; Martin, GC Macromolecules, 1989, 22 99-104; Heise, MS; Martin, GCJ Poly. Sci .: Part C) Polym. Lett. 1988, 26, 153-157; Barton, JM; Shepherd, PM; Die Makromolekular Chemie 1975 176, 919-930). However, one of the drawbacks is that they can be used directly in one-component adhesives because they are so effective as curative that once they are added they will initiate the kick-off of curing in a relatively short time. It is not. Since Hardner continues to accelerate the ring-opening polymerization of epoxy moieties, one skilled in the art would like to prepare adhesives and films thereof, but one skilled in the art observes that the viscosity of the composition increases slowly. This phenomenon is most commonly referred to as reduced workable life, ie the time available to assemble the adhesive and make the film has been dramatically reduced because of premature curing. Thus, in order to stop this from happening, in general, the amine-epoxy adduct itself is not used as a hardener, but instead is usually done by encapsulating or coating the amine-epoxy adduct with a protective shell of material that isolates it from the adhesive environment. . Once incorporated into the adhesive, the amine-epoxy adduct is released from its protective shell through the application of heat and / or pressure. The latent hardeners described herein are commonly referred to as core-shell latent hardeners, in which case the core is an amine-epoxy adduct and the shell is a protective shell.

One important trade-off faced by core-shell latent hardeners is that the rate of cure is often due to the inclusion of a protective shell that must be broken or permeable in order for the core material to be released into the adhesive environment or matrix. The curing temperature is often increased. Without wishing to be bound by any particular theory, using the aforementioned means, for example, to increase the shell thickness, crosslink density or T _g of the shell or increase the degree of incompatibility between the shell and the core material or adhesive matrix. It is well known that more energy is required to release the amine-epoxy adduct into the adhesive environment, thereby increasing the barrier properties of the shell material. Thus, when formulated as a one-part adhesive, it is a hardener with increased shelf life stability, which is a desired property at the expense of low cure temperature and a decrease in cure rate. Thus, a constant balance is maintained to produce core-shell latent hardeners with sufficient protective shells to protect the core material under normal storage conditions but not too much to slow down the curing rate of the adhesive. In addition, release of the core material can be reasonably triggered at low temperatures and completed within a narrow temperature range.

One of the most frequently used core-shell latent hardeners is US Pat. No. 4,833,226, US Pat. No. 5,219,956, US 2006/0128835, US 2007/0010636, US 2007/0055039, US 2007 /. Those composed of core-shell materials as described in 0244268, EP 1,557,438, EP 1,731,545, EP 1,852,452, and EP 1,980,580. The hardeners described herein are first obtained by the synthesis of a lump of core material, which is then milled into microsized particles of irregular shape. The core material is the reaction product of the amine compound and the epoxy resin, and the core material described above functions as a hardener for the epoxy composition, as found in adhesives and coatings. To improve the storage stability of the core material and to prevent premature curing, it is encapsulated in a shell of material impermeable to components of the epoxy composition, such as solvents, diluents, low molecular weight epoxides and additives. To achieve this, the milled solid is added to a mixture of polyfunctional isocyanates, active hydrogen compounds such as water, and epoxy resins. The chemistry of the encapsulation process depends on the crosslinking reaction and / or hydrolysis of the polyisocyanate compound to form a crosslinked shell coating around the particles. Conventional crosslinking structures of the shell include, but are not limited to, urea, urethane, carbamate, biuret, allophanate, and the like. However, crosslinking reactions occur randomly in the continuous phase and without discrimination at the interface. Unnecessary by-products such as crosslinked polyurea particles are produced in the continuous phase, while some core particles are very unlikely to be fully encapsulated. In addition, the core particles produced by this process are irregular shapes having a very wide distribution of shapes and particle sizes, and the uniformity of the thickness and crosslink density of the shell formed thereon is very poor. As a result, encapsulated hardener particles typically exhibit a very wide range of release properties, and single-component adhesives formulated with these types of hardener capsules often exhibit poor shelf life stability and inadequate cure profiles or high cure temperatures.

Unlike the above, other groups of the invention which also describe core shell latent hardeners that are spherical in shape, ie EP 459,745, EP 552,976, US 5,357,008, US 5,480,957, US 5,548,058, US 5,554,714, 5,561,204, US 5,567,792 and US 5,591,814. The core material is obtained as spherical particles and synthesized from the reaction of an amine with an active hydrogen atom (eg imidazole) and an epoxy resin in the presence of a dispersant in an organic medium. The amines, epoxy resins and dispersants are soluble in the organic medium, while the reaction products, not the core material, as a result of which the core particles precipitate out of solution as a stable dispersion with a relatively narrow size distribution. The most important factor for producing a stable dispersion of the preferred particle size with a narrow size distribution is the nature of the dispersant, and the inventors have found that the graft of polyacrylate, polyacrylamide, polyvinyl acetate, polyethylene oxide, polystyrene and polyvinyl chloride Examples of using dispersants from the class are given. Once separated, the spherical core material is encapsulated with isocyanates to produce spherical core-shell latent hardeners.

The shell material should not contain defects, for example holes, voids, thin regions, or regions consisting of insufficient crosslink density. Such defects may allow the core to be released early from the protective shell during processing or storage of the finished product. Either way, early release of these cores from the encapsulated latent hardener will result in loss of storage stability and shelf life (in the case of one-part epoxy adhesives). However, this defect can be overcome by applying an additional and continuous layer of shell material to the previously existing shell and thus filling and covering the additional layer of shell material with the defect.

Another limitation of the prior art is that, in attempts to produce more impermeable protective shells and to improve their barrier properties, the compatibility of the shells with the surrounding epoxy compositions has been ignored. The prior art teaches encapsulation in the presence of isocyanates and optionally water and further epoxy. What is obtained is a shell composed of crosslinked polyurethane and optionally polyurea. When formulated with epoxy adhesives, currently hard, highly crosslinked shells have poor ability with the surrounding epoxy. An example of this is a mismatch of the surface tension between the surface of the shell and the epoxy, which will appear as a dewetting phenomenon where the epoxy is dispersed on the surface of the shell material without being adequately wetted. Thus, as a result, it will be appreciated that after curing, the adhesive will contain voids and heterogeneous cured regions, both of which will reduce the adhesive strength.

There is still a need for core-shell latent hardeners with improved barrier properties to prevent premature curing. In addition, there is a need for encapsulated latent hardeners with improved epoxy compatibility.

SUMMARY OF THE INVENTION

The present invention relates to latent hardeners or catalysts for thermosets, for example epoxy resins, more particularly latent hardeners or catalysts composed of a core material encapsulated or coated with a shell material. The curable core material for epoxy resins further consists of the reaction product of amines such as imidazole, piperazine, primary aliphatic amines, and secondary aliphatic amines and epoxy resins. In one embodiment, the core material is synthesized in the presence of a dispersant that is a reaction product of carboxyl terminated poly (butadiene-co-acrylonitrile) (CTBN) and an epoxy resin in an organic medium. In one embodiment, the reaction product of CTBN and epoxy resin can provide a stable dispersion of spherical core particles of narrow size distribution. In another embodiment, nearly 100% conversion is obtained using a slight excess of epoxy. In another embodiment, the spherical core particles are encapsulated by reaction with polyfunctional isocyanates or thioisocyanates. Optionally, an epoxy resin is added simultaneously with the isocyanate to enhance the thickness of the encapsulated shell. In another embodiment, once formed, the core material may be a polyfunctional isocyanate, or a mixture of isocyanates and a polyfunctional epoxy resin, or a mixture of isocyanates and epoxy compatible materials, such as CTBN or polyacrylate modified epoxy, or It is fully encapsulated into two or more shell materials applied in a stepwise manner using a mixture of isocyanates, multifunctional epoxy and epoxy compatible materials. Curable compositions prepared using the particles have excellent storage stability and improved curability.

One aspect of the present disclosure relates to improvements in barrier properties and solvent resistance of latent hardeners or catalysts.

Another aspect of the present disclosure relates to improvements in barrier properties and solvent resistance of latent hardeners or catalysts.

Another aspect of the present disclosure is directed to improvements in the compatibility of latent hardeners or catalysts with epoxy resins or compositions.

Another aspect of the present disclosure relates to spherical and fully encapsulated latent hardeners or catalysts.

Another aspect of the present disclosure relates to latent hardeners or catalysts that release the core material at the desired temperature, pressure, or a combination of both.

Another aspect of the present disclosure relates to latent core-shell latent hardeners or catalysts, wherein the hardeners or catalysts consist of a stable dispersion of spherical particles.

Another aspect of the present specification relates to a method for producing spherical core particles using a dispersant, wherein the dispersant is a reaction product (adduct) of a carboxyl-terminated butadiene-acrylonitrile rubber (CTBN) and an epoxy resin.

Another aspect of the present specification relates to a curing agent composed of an amine compound, an epoxy resin, and a dispersant, wherein the dispersant is an adduct of CTBN and an epoxy resin.

Another aspect of the present specification relates to a method of preparing a curing agent.

Another aspect of the present disclosure relates to a masterbatch composed of a curing agent.

Another aspect of the present disclosure relates to an electronic device or flat panel display comprising a composition comprised of the curing agent described herein. For example, conventional methods used to connect driver integrated circuits (ICs) to electronic devices or flat panel displays are chip-on-glass (COG) or chip-on-film (COF) chip. through the use of -on-film). In the construction of COGs and COFs, anisotropic conductive film adhesives (ACFs) and non-conductive film adhesives (NCFs) are commonly used to attach COGs or COFs to driver ICs, which cure the adhesive and create permanent bonds between components. It is a hardener. Thus, in one embodiment, an integrated circuit chip or other electronic component is attached using an epoxy adhesive containing a curing agent described herein.

Another aspect of the present disclosure relates to a composition containing a curing agent, wherein the composition is an adhesive, a conductive adhesive, a composite, a molding compound, an anisotropic conductive film (ACF) adhesive, a non-random array ACF, a non-conductive adhesive film ( NCF), coatings, encapsulants, underfill materials, lead or glass solder.

Another aspect of the present disclosure relates to a circuit board comprising an epoxy adhesive composition composed of a curing agent described herein. Typically, electronic components such as resistors, capacitors, and ICs are assembled to a circuit board through a soldering process. This process requires high temperatures and generates waste. However, the described ACF, NCF or conductive adhesives containing hardeners provide an alternative method of mounting electronic components on circuit boards without heavy metals of high temperature use, waste and toxicity. In this application, the ACF and NCF provide electrical contact and secure the part to the substrate.

Another aspect of the present disclosure relates to an electronic device or display assembled using an epoxy adhesive composition containing a curing agent described herein.

Another aspect of the present disclosure relates to a flip chip comprising an adhesive composition containing a curing agent described herein. Typically, flip chips are chips mounted on a substrate in two steps. First, the chip is bonded to the substrate via soldering or eutectic bonding. The underfill material is then filled in a gap between the chip and the substrate, typically in liquid form, and cured. Replacing the soldering or eutectic bonding process with ACF or NCF containing the curing agent described herein is an alternative method to achieve the first step. Not only does the adhesive approach provide the advantages that the circuit board faces, ACF and NCF also function as the underfill material to fill the gap between the chip and the substrate to achieve the process in a single step, and two steps were previously used.

Another aspect of the present disclosure is directed to an electronic device or display composed of a curing agent, wherein the composition is not cured, partially cured or cured.

Another aspect of the present disclosure is a flip chip in which a high resolution LCD, an electronic paper (ePaper), a mini projector, and a flat panel display, an electronic device, a circuit board, and an epoxy adhesive containing a curing agent described herein are used as described above. It relates to a semiconductor device such as a mobile phone.

Another aspect of the present specification is a fixed array ACF, wherein the fixed array ACF is an epoxy adhesive containing gold particles in a predetermined pattern on an adhesive film, for example, containing a curing agent as described herein to build an array. Dispersed ACF as described in Trillion patent application 2006/0280912 Al.

Another aspect of this specification is a high T _g one component molding compound comprising a protected phenolic compound described in US Application No. 12 / 008,375, filed Jan. 10, 2008, which is incorporated herein by reference. , Wherein the phenolic compound protected includes aryl glycidyl carbonate residues, and the curing agents described herein.

Another aspect of the present disclosure includes a prepreg composite and molding compound, such as sheet molding compound (SMC), bulk molding compound (BMC) and dough molding compound (DMC). It is a liquid complex, wherein the curing agent is the curing agent described herein.

Another aspect of the present specification is an adhesive and a coating article comprising a solder mask and an impregnating coating, wherein the curing agent is the curing agent described herein.

Another aspect of the present specification includes a curing agent described herein in an assembly, for example, see Colclaser, Roy A .; "Microelectronics Processing and Device Design"; John Wiley & Sons, Publishers: New York, 1980; Chapter 8, page pp. 163-181), uses an epoxy resin for packaging a semiconductor article.

Another aspect of the present disclosure relates to a circuit board composed of the curing agent described herein, wherein the composition is not cured, partially cured or cured.

Another aspect of the present disclosure relates to a flip chip composed of a curing agent, wherein the epoxy adhesive composition described herein is not cured, partially cured or cured.

Another aspect of the present disclosure relates to a semiconductor device comprising a composition containing a curing agent. Another aspect of the present disclosure relates to a semiconductor device wherein the composition is cured, partially cured or not cured and consists of a curing agent.

Another aspect of the invention relates to a composition, wherein the composition is a one-part adhesive composition having a substantially long shelf life under storage conditions, and is reactive at a curing temperature or molding temperature and contains a curing agent as described herein.

Another aspect of the present disclosure relates to a composition containing a curing agent, wherein after curing, the composition exhibits adhesion at the interface, low shrinkage upon curing, and low coefficient of thermal expansion (CTE).

A further aspect of the present disclosure relates to a composition containing a curing agent, wherein the composition is a matrix for a composite material or a molding compound.

1 shows a core material encapsulated with two protective shell materials. For improved latent hardner compatibility, the composition of protective shell 2 is chosen to consist of an epoxy compatible material, and the composition of shell 1 is chosen only based on its barrier properties.
FIG. 2 is an electron micrograph of spherical core particles composed of 2-methylimidazole, diglycidyl ether of bisphenol A (DGEBA) and CTBN-epoxy adducts isolated from CVC Thermoset Materials HyPox ™ RK84.
FIG. 3 is an electron micrograph of spherical core particles consisting of 2-methylimidazole, diglycidyl ether of bisphenol A (DGEBA) and CTBN-epoxy adducts isolated from CVC Thermoset Materials HyPox ™ RK84, where the core particles Is encapsulated with 4,4'-methylenebis (phenyl isocyanate) (MDI).
4 is an electron micrograph of spherical single core particles consisting of 2-methylimidazole, diglycidyl ether of bisphenol A (DGEBA) and CTBN-epoxy adducts isolated from CVC Thermoset Materials HyPox ™ RK84.
FIG. 5 is the chemical structure of CTBN-epoxy adduct (c), where it is used in synthesis with CTBN (a) which is of hydroxyl-functional epoxy resin (b), eg, CVC Thermoset Specialties HyPox RK84. . The remaining unreacted epoxy resin (b) is removed before (c) is used as a dispersant.
FIG. 6 is the chemical structure of CTBN-epoxy adduct (e), wherein diglycidyl ether (d) of bisphenol A, for example CVC Thermoset Specialties HyPox RA1340, is used for synthesis with CTBN (a). .

In one embodiment, the curing agent is an adduct consisting of (i) an amine, (ii) an epoxy compound and (iii) an adduct of an elastomer and an epoxy resin. The elastomer / epoxy resin adduct serves as a reactive dispersant that allows the formation of a dispersion of spherical unencapsulated particles in the reaction medium.

Another aspect of the present invention provides a fine spherical core of a curing agent comprising reacting an amine compound with an epoxy / elastomer adduct followed by an epoxy compound while shaking in the presence of a continuous phase at elevated temperature and recovering the fine spherical particles formed from the reaction mixture solution. It is a manufacturing method of particle | grains. Optionally, the recovered particles can be filtered to remove aggregated particles and sorted by methods such as gravity fractionation, filtration, sedimentation, field flow fractionation and field flow fractionation to remove small satellite particles. have. The continuous phase is an organic solvent or solvent mixture consisting of a solvent capable of dissolving an amine compound, an epoxy compound, and an epoxy / elastomer adduct but not capable of dissolving the adduct formed from three reactants or a mixture of solvent and non-solvent, wherein the The solvent may dissolve the amine compound, the epoxy compound and the epoxy / elastomer adduct, but the adduct particles formed from the three reactants or mixtures cannot dissolve, and the non-solvent is the amine compound, the epoxy compound, the epoxy / elastomer adduct. And non-solvents for adduct particles formed from the three reactants. The choice of continuous phase affects dispersion stability and particle size and particle size distribution.

Another aspect of the present invention is a thermosetting composition comprising spherical particles of an epoxy composition and a curing agent as its main components. In this case, the spherical particles of the curing agent of the present invention are not soluble or swellable in the epoxy composition. In one embodiment, the melt flow temperature of the particles is at least about 50 ° C. and the particle diameter is 0.1 μm to 30 μm. The particles are introduced into the adhesive in an amount of about 1 to 60 parts by weight per 100 parts by weight of epoxy resin.

In one embodiment, the present invention also includes a curing agent masterbatch for an epoxy resin, wherein the masterbatch comprises a liquid epoxy resin in which fine spherical particles of the curing agent are uniformly dispersed. In certain embodiments, the particles were reacted with 1 to 100 parts by weight of the polyfunctional isocyanate compound and optionally 1 to 100 parts by weight based on 100 parts by weight of the particles described above. The particles are then subjected to continuous steps with 1 to 100 parts by weight of the polyfunctional isocyanate compound, and optionally 1 to 100 parts by weight of the multifunctional epoxy compound and optionally 1 to 100 parts by weight of the epoxy compatible material, based on 100 parts by weight of the particles. The reaction is carried out one or more times.

The present invention further includes a method for producing a curing agent masterbatch for an epoxy resin comprising dispersing spherical particles of the curing agent in an epoxy resin at a temperature below the melt flow temperature of the spherical particles.

Curing Agent Epoxy + Amine Compound

In the present invention, the amine compound and the epoxy compound which can be used in the preparation of the curing agent have its chemical structure which promotes the curing reaction by anionic polymerization, its melting point and its compatibility with the epoxy resin cured to a molten or plasticized viscoelastic state. It is selected based on the sex, its quick cure and its reactivity. Melt flow temperature is defined herein as the temperature at which material begins to flow as molten fluid, as measured by conventional methods. Examples of amines and epoxy compounds useful in certain embodiments of the present invention include EP 459,745, EP 552,976, US 5,357,008, US 5,480,957, US 5,548,058, US 5,554,714, 5,561,204, US 5,567,792 and US 5,591,814.

Amine compound

While any amine compound can be used, the choice of amine is based on the properties of the epoxy compound. An amine is selected that reacts with the epoxy compound but allows the reaction without complete polymerization. When reacting with a monofunctional epoxy compound, substantially any amine compound can be used, but when reacting a polyfunctional epoxy compound, the secondary amino contributing to the reaction of an amine compound with only one active hydrogen, ie an epoxy group You can use groups. The use of compounds with tertiary amino groups, ie without active hydrogen at all, is also acceptable. The following compounds are illustrative examples of amine compounds that may be combined with bifunctional bisphenol A diglycidyl ethers: imidazoles represented by 2-methylimidazole and 2,4-dimethylimidazole, N-methyl piperazine And piperazine represented by N-hydroxyl ethyl-piperazine, ananacin represented by anabacin, pyrazole represented by 3,5-dimethyl-pyrazole, purine represented by tetra-methyl-quaanidine or purine, Pyrazoles represented by pyrazoles, triazoles represented by 1,2,3-triazoles, and the like.

Epoxy compound

Examples of epoxy compounds include monofunctional epoxy compounds such as n-butyl glycidyl ether, styrene oxide and phenylglycidyl ether; Bifunctional epoxy compounds such as bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether and diglycidyl phthalate; Trifunctional compounds such as triglycidyl isocyanurate, triglycidyl p-aminophenol; Tetrafunctional compounds such as tetraglycidyl m-xylene diamine and tetraglycidyldiaminodiphenylmethane; And compounds with additional functional groups such as cresol novolac polyglycidyl ether, phenol novolac polyglycidyl ether and the like. The choice of epoxy is also determined by the type of amine compound to be blended. Epoxy compounds are also selected in the molten state with respect to the epoxy resin to cure based on the softening point and compatibility of the adducts formed. Since most of the epoxy resins to be cured include bisphenol A diglycidyl ether, this compound is most commonly used as a starting material for preparing adducts. In one embodiment, epoxy compounds having an epoxy equivalent weight of at most about 1,000, preferably at most about 500, are commonly used.

menstruum

Although it is possible to dissolve the amine compound and the epoxy compound as starting materials, it is also important to choose a solvent system that can precipitate the adduct in the form of particles without dissolution. Examples of solvents that may be used in certain embodiments of the invention include methyl isobutyl ketone, methyl isopropyl ketone, methyl ethyl ketone, acetone, n-butyl acetate, isobutyl acetate, ethyl acetate, methyl acetate, tetrahydrofuran, 1, 4-dioxane, cellosolve, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, anisole, toluene, p-xylene, benzene, methylene chloride, chloroform, trichloroethylene, chlorobenzene and pyridine. These solvents may be used alone, or two or more solvents may be used together.

Non-solvent

In addition, it is necessary to add a non-solvent so that the amine compound reacts with the dispersion stabilizer and the epoxy functional groups of the epoxy resin. In this case the non-solvent is any solvent that does not dissolve the amine compound, dispersion stabilizer or epoxy resin. One possible class of compounds that can be used as non-solvents are linear or branched chain aliphatic compounds such as heptane, hexane, octane, iso-octane, petroleum ether and the like. One example of a non-solvent with a solvent is a mixture of heptane and MIBK. In addition to the solvents and non-solvents described above, diluents or dilute solvents may optionally be used to widen the formulation or process window.

Dispersion stabilizers or dispersants

Dispersion stabilizers or dispersants enable stable dispersion of adduct particles in the reaction medium. Without this dispersion stabilizer, the adduct particles formed can agglomerate and precipitate into viscous masses during the reaction, and thus the desired fine spherical particles cannot be obtained. Optimal dispersants are important for producing stable dispersions with narrow particle size distributions. Reactive dispersants are often more effective than non-reactive dispersants because there is little desorption or migration of the dispersant away from the particle surface once it has reacted with the particulate phase. Elastomer / epoxy adducts are used according to the invention as reactive dispersants. Suitable molecular weight ranges for the reactive dispersant are about 1,000 to 300,000, preferably about 2,000 to 100,000, most preferably about 3,000 to 10,000.

Epoxy / Elastomer Additives as Reactive Dispersants

The epoxy / elastomer adduct itself generally comprises about 1: 5 to 5: 1 parts epoxy or other polymer to elastomer, more preferably about 1: 3 to 3: 1 parts epoxy to elastomer. More typically, the adduct comprises at least about 5%, more typically at least about 12%, even more typically at least about 18%, and also typically at most about 50%, even more typically at most about 40%, Even more typically, up to about 35% of the elastomer is included, although high or low ratios are possible. Elastomers suitable for the adduct may be functionalized in the main chain or in the side chain. Suitable functional groups include -COOH, -NH ₂ , -NH-, -OH, -SH, -CONH ₂ , -CONH-, -NHCONH-, -NCO, -NCS, and oxirane or glycidyl groups, and the like. Including but not limited to. The elastomer may be optionally vulcanizable or postcrosslinkable. Exemplary elastomers include, without limitation, natural rubber, styrene-butadiene rubber, polyisoprene, polyisobutylene, polybutadiene, isoprene-butadiene copolymer, neoprene, nitrile rubber, butadiene-acrylonitrile copolymer, butyl rubber, poly Sulfide elastomers, acrylic elastomers, acrylonitrile elastomers, silicone rubbers, polysiloxanes, polyester rubbers, diisocyanate-bonded condensation elastomers, ethylene-propylene diene rubbers (EPDM), chlorosulfonated polyethylene, fluorinated hydrocarbons, thermoplastic elastomers, for example Such as (AB) and (ABA) forms of block copolymers of styrene and butadiene or isoprene, (AB) n forms of multi-segment block copolymers of polyurethane or polyester, and the like. When carboxyl terminated butadiene-acrylonitrile (CTBN) is used as the functionalized elastomer, the preferred nitrile content is 12 to 35% by weight, more preferably 20 to 33% by weight.

Examples of preferred epoxide-functionalized epoxy / elastomeric adducts are mixtures with epoxy resins under the tradename HyPox ™ RK84 (FIG. 5), bisphenol A epoxy resins modified with CTBN elastomers, and tradename HyPox ™ RA1340 (FIG. 6), CTBN elastomers And commercially available from CVC Thermoset Specialties (Moorestown, NJ). In addition to bisphenol A epoxy resins, other epoxy resins include epoxy / elastomeric adducts such as n-butyl glycidyl ether, styrene oxide and phenylglycidyl ether; Bifunctional epoxy compounds such as bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether and diglycidyl phthalate; Trifunctional compounds such as triglycidyl isocyanurate, triglycidyl p-aminophenol; Tetrafunctional compounds such as tetraglycidyl m-xylene diamine and tetraglycidyldiaminodiphenylmethane; And compounds having additional functional groups such as cresol novolac polyglycidyl ether, phenol novolac polyglycidyl ether, and the like. Examples of additional or alternative epoxy / elastomers and other adducts suitable for use in the present invention are described in US Pat. No. 6,846,559 and C. Patent Publications of Czaplicki, Michael, all of which are incorporated herein by reference. 2004/0204551.

Amine Compounds + Reactive Dispersants

To prepare the curing agent, in one non-limiting process, the selected amine compound and the epoxide-functionalized reactive dispersant are first reacted to ensure that the dispersant is fully introduced. The reactive dispersant is dissolved in the selected solvent system and reacted using a combination of heating and stirring for about 2 minutes to about 3 hours, preferably about 4 minutes to about 2 hours, most preferably about 5 minutes to about 1 hour. I was. Accordingly, reaction temperatures that can be used in the present invention are typically from 40 ° C. to 90 ° C., preferably from 50 ° C. to 80 ° C., and the concentrations of the starting materials, ie the amine compound and the epoxide-functionalized reactive dispersant, are typically about 2 To 40% by weight, preferably about 5 to 30% by weight. The amount of the reactive dispersant is about 1 to 70% (w / w) based on the combined weight of the reactive dispersant and the amine compound, preferably about 5 to 50% based on the combined weight of the reactive dispersant and the amine compound. (w / w), most preferably about 9 to 35% (w / w) based on the combined weight of the reactive dispersant and the amine compound. In special cases where the epoxide-functionalized reactive dispersant contains a residual epoxy compound that is not bonded to the elastomer, further purification consists of removing the unreacted epoxy compound from the reactive dispersant described above, for example, in FIGS. 5 and 6. Start the step. This purification step is especially important to avoid the formation of aggregates and aggregates of solid materials after the addition of epoxy compounds (see below).

Epoxy compatible materials

Epoxy compatible materials are any epoxy-functional materials containing functional groups or groups compatible with epoxy resins. One example is an epoxide-functionalized epoxy / elastomeric adduct commercially available as a mixture with an epoxy resin commercially available from CVC Thermoset Specialties (Moorestown, NJ) under the tradename HyPox ™ RK84 (FIG. 5) and the trade name HyPox RA1340 (FIG. 6). to be. The HyPox elastomers described above contain epoxy compatible monomer acrylonitrile. Other examples include, but are not limited to, epoxy compatible comonomers such as epoxy-functional polyacrylates containing acrylonitrile and methyl methacrylate.

Amine Compound + Epoxide-functionalized Reactive Dispersant + Epoxy Compound, Formation of Unencapsulated Particles

After reacting the amine compound with the epoxide-functionalized dispersant, the formation of unencapsulated latent hardener particles begins with the addition of an epoxy compound. The solution of the epoxy compound is about 5 minutes to 6 hours, preferably about 10 minutes to 4 hours, most preferably using an apparatus that allows constant continuous addition of the epoxy resin solution, such as a syringe pump or peristaltic pump, etc. Is slowly added to the stirred heated solution of the amine compound-dispersion stabilizer solution over about 15 minutes to 2 hours. The amount of epoxy compound is about 10 to 90% (w / w), preferably about 30 to 85% (w / w), most preferably based on the combined weight of the amine compound, the reactive dispersant and the epoxy compound. Is about 50-80% (w / w). In one example, a solution of the reactive dispersant and the amine is shaken while heating under an inert atmosphere, and after a predetermined time, a solution of the epoxy compound is added for a predetermined time. The original clear solution becomes opaque as the epoxy compound begins to react. As the reaction proceeds, the opacity of the reaction system gradually increases with the unique milky turbid dispersion eventually produced.

If the reaction temperature and concentration of the starting material is too high, aggregates can easily form even in the presence of a suitable amount of reactive dispersant. Thus, the reaction temperatures that can be used in the present invention are typically from 40 ° C. to 90 ° C., preferably from 50 ° C. to 80 ° C., and the concentrations of the starting materials, ie the amine compounds, the reactive dispersants and the epoxy compounds, are usually from 2 to 40 weight. %, Preferably 5 to 30% by weight. In general, the particle size of the adduct increases with increasing concentration of the starting material but decreases with increasing concentration of the reactive dispersant.

Encapsulation

The particles are subsequently encapsulated while applying each layer of the encapsulation or protective shell onto the particles in one or more successive steps. Various known methods of encapsulating spherical curing agents can be used in the present invention. In one embodiment, the adduct particles can be reacted step-wise with the encapsulating agent to form two or more protective shells, wherein the encapsulating agent is a polyfunctional isocyanate compound or a polyfunctional isocyanate compound and a multifunctional epoxy. Mixtures of compounds or mixtures of polyfunctional isocyanates with epoxy compatible compounds such as acrylonitrile or mixtures of polyfunctional isocyanates, epoxy compounds and epoxy compatible compounds. Suitable polyfunctional isocyanate compounds include toluene diisocyanate, methylene diphenyl diisocyanate, hydrogenated methylene diphenyl diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylyl Ethylene diisocyanate, tetramethylxylene diisocyanate, 1,3,6-hexamethylene triisocyanate, lysine diisocyanate, triphenylethane triisocyanate, polyfunctional isocyanate compounds formed by the addition of these compounds and other active hydrogen-containing compounds and these Mononuclear species and multinuclear species of any mixture of;

Representative examples of multifunctional epoxies are methylene bisglycidyl aniline, HELOXY ™ Modifier 48 (from Hexion Specialty Chemicals), Toagosei GP-301 graft polymethylmethacrylate-g-epoxy modified acrylate Polyfunctional epoxies containing polymers and acrylonitrile (epoxy compatible comonomers) are included, but other multifunctional epoxies should also be included.

The amount of encapsulating agent used to encapsulate the unencapsulated particles affects the storage stability and curability of the curing agent masterbatch. With the addition of the same particles, increased amounts of encapsulating agent improve storage stability but lower curability. Thus, for adduct particles of about 0.1 μm to 30 μm in diameter, the encapsulating agent is about 50:50 to 95: 5 (w / w) of core particles to encapsulating agent, preferably about 60:40 of core particles to encapsulating agent. To 90:10 (w / w), most preferably a ratio of core particles to encapsulant about 70:30 to 90:10 (w / w). In addition, when the encapsulating agent is an isocyanate compound and an epoxy compound or a mixture of an isocyanate compound and an epoxy compatible compound, the amount of the epoxy compound is about 1:99 to 99: 1 (w / w), preferably isocyanate Compound to epoxy compound about 60:40 to 99: 1 (w / w), most preferably isocyanate compound to epoxy compound about 80:20 to 99: 1 (w / w). In addition, when the encapsulating agent is a mixture of isocyanate, epoxy compound and epoxy compatible compound, the amount of epoxy compound is about 1:99 to 99: 1 (w / w), preferably isocyanate compound to epoxy compound + Epoxy compatible compounds about 60:40 to 99: 1 (w / w), most preferably in an ratio of isocyanate compound to epoxy compound about 80:20 to 99: 1 (w / w). Thus, the compromise between storage stability and curability varies with the size of the adduct particles, and smaller particle sizes require increased amounts of shell forming material, for example polyfunctional isocyanates, to achieve the same release or barrier properties. Shall be.

In one embodiment, upon completion of the particle formation reaction, the unencapsulated particles are separated from the reaction medium by filtration and then washed with fresh solvent. The particles are subsequently encapsulated.

Masterbatch

Generally, in order to form a masterbatch, the encapsulated particles are formulated at about 5 to 90% (w / w), preferably based on the combined weight of the particles and the epoxy resin, preferably the particles and the liquid epoxy compound. Based on the total weight of the epoxy, in the range of about 20 to 70% (w / w), most preferably based on the combined weight of the particles and the liquid epoxy compound. Disperse uniformly in resin.

In one embodiment, the epoxy resin can be one or more epoxy resins such as bisphenol A, bisphenol F, novolac epoxy, and the like.

In one embodiment, to avoid the formation of secondary particles, the encapsulated particles are mechanically dispersed in an epoxy resin as primary particles, for example by blending with a 3-roll mill.

In another embodiment, after the encapsulation process is complete, heating and stirring are stopped and the epoxy resin is added to the dispersion. The mixture is stirred again again sufficiently to evenly distribute the epoxy resin in the dispersion. The solvent is then removed using vacuum distillation or the like so that the total solids content is from about 60 to 100% (w / w), preferably from about 70 to 100% (w / w), most preferably from about 80 to 100% (w / w). The particles are then further dispersed in the epoxy resin using techniques known to those skilled in the art, such as a 3-roll mill or the like.

In another embodiment, upon completion of the reaction, the solvent is removed by vacuum distillation to a solid content of 100% (w / w). Solid particles are then added to the epoxy resin and the particles are further dispersed in the epoxy resin using techniques known to those skilled in the art, such as a 3-roll mill or the like.

In another embodiment, upon completion of the reaction, the dispersion of particles is filtered to separate the particles. Fresh solvent is used to wash the unreacted starting material attached to the surface of the particles. The epoxy resin is then added to the solid particles and the mixture is further dispersed using techniques known to those skilled in the art, such as a 3-roll mill or the like.

The adhesive compositions described herein include conductive adhesives, composites, molding compounds, anisotropic conductive film (ACF) adhesives, non-random array ACFs, non-conductive adhesive films (NCFs), coatings, encapsulants, underfill materials, lead-free solders Potentially useful for a variety of applications, including and the like.

Having described the invention in detail, the invention is illustrated by the following non-limiting examples:

Example

Example of Formation of Unencapsulated Core Particles:

Example 1 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (1)

Commercial material HyPox RK84 (commercial material from CVC Thermoset Specialties and bisphenol A epoxy resin and adducts thereof and a mixture of CTBN (FIG. 5)) was used as dispersion stabilizer. In a three neck round bottom flask equipped with PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropwise funnel and argon gas inlet, 0.93 g of CTBN-epoxy adduct, 1.64 g (0.02 mol) of 2-methylimidazole and 48 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 3.39 g (0.019 equiv) of DER ™ 332 (Dow Chemical) and 3.4 g MIBK was added dropwise over 20 minutes, then the reaction was stirred under an argon atmosphere for 6 hours at 300 rpm. did. A milky white dispersion formed. The dispersion was withdrawn from the reactor, centrifuged, washed with MIBK and evaporated to dryness to yield 3.6 g (60.4% yield) of product. The droplets of dispersion were diluted, coated on a glass slide and dried under vacuum at room temperature. The dried sample was sputtered with a thin layer of gold, and scanning electron micrographs thereof were obtained using a Hitachi S-2460N scanning electron microscope.

Example 2. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (2)

CTBN-epoxy adduct isolated from CVC Thermoset Specialties HyPox ™ RK84 was used as dispersion stabilizer. The material was dissolved in methyl ethyl ketone and then precipitated with methanol and the process repeated two more times to give the adduct. Unencapsulated core particles (2) were obtained from Example 1 from 0.51 g of CTBN-epoxy adduct, 1.63 g (0.02 mol) of 2-methylimidazole, 3.51 g (0.02 equivalent) of DER ™ 332 and 51 g of MIBK. Synthesis using the process of yielded 4.4 g (78% yield) of particles.

Example 3. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RA1340 (3)

Commercial material HyPox RA1340 (commercial material from CVC Thermoset Specialties, and diglycidyl ether of bisphenol A and its by-product and mixture of CTBN (FIG. 6)) was used as dispersion stabilizer. Microcapsule core 3 was prepared from 1.15 g of the CTBN-epoxy adduct described above, 1.64 g (0.02 mol) of 2-methylimidazole, 2.87 g (0.0164 equivalents) of DER ™ 332 and 51 g of MIBK. Synthesis using the process of afforded 1.2 g (21.2% yield) of particles.

Example 4 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RA1340 (4)

CTBN-epoxy adduct isolated from CVC Thermoset Specialties HyPox ™ RA1340 was used as dispersion stabilizer. The adduct was obtained by first dissolving the material in methyl ethyl ketone, then precipitating with methanol and repeating this process two more times. Unencapsulated core particles (4) were prepared in Example 1 from 0.53 g of CTBN-adduct, 1.65 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 and 51 g of MIBK. Synthesis using the procedure described gave 2.6 g (45.9% yield) of particles.

Example 5 Synthesis of Unencapsulated Core Particles from 2-Ethyl-4-methylimidazole, DGEBA and HyPox ™ RK 84 (5)

Unencapsulated core particles (5) consisted of 0.57 g of Example 2 CTBN-epoxy adduct, 2.20 g (0.02 mol) of 2-ethyl-4-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 And 63 g of MIBK were synthesized using the process of Example 1 to yield 0.7 g (11.2% yield) of particles.

Example 6 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RA1340 (6)

Unencapsulated core particles 6 consisted of 0.26 g of CTBN-epoxy adduct of Example 4, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equivalent) of DER ™ 332 and 50 g of MIBK Synthesis was carried out using the process of Example 1 from to obtain 1.6 g (26.9% yield) of particles.

Example 7 Synthesis of Unencapsulated Core Particles from 2-Ethyl-4-methylimidazole, DGEBA and HyPox ™ RK 84 (7)

Unencapsulated core particles (7) consisted of 0.57 g of the CTBN-epoxy adduct of Example 2, 2.20 g (0.02 mol) 2-ethyl-4-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 And 56 g of MIBK were synthesized using the process of Example 1, and the reaction was stirred at 300 rpm for 16.5 hours under an argon atmosphere to yield 2.5 g (40% yield) of particles.

Example 8 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (8)

The microcapsule core 8 is run from 0.52 g of the CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 and 51 g of MIBK It synthesize | combined using the process of Example 1. The reaction was stirred at 300 rpm for 16 h under argon atmosphere to yield 4.0 g (71% yield) of particles.

Example 9 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (9)

Unencapsulated core particles 9 were 0.52 g of the CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 and 52 g of MIBK It synthesize | combined using the process of Example 1 from the. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere to yield 4.18 g (74% yield) of particles.

Example 10. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (10)

Unencapsulated core particles 10 consisted of 0.52 g of Example 2 CTBN-epoxy adduct, 1.64 g (0.02 mol) of 2-methylimidazole and 37.3 g of 4-methyl-2-pentanone (MIBK) Synthesized from The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 3.5 g (0.02 equiv) of DER ™ 332 (product of Dow Chemical) and 3.5 g MIBK was added dropwise over 15 minutes, then the reaction was stirred at 1000 rpm for 1 hour under argon atmosphere. Thereafter, 10 g of heptane was added dropwise over 1 hour. The reaction was stirred at 1000 ppm for an additional 4 hours. A milky white dispersion formed. The dispersion was drained, centrifuged, washed with MIBK and evaporated to dryness to yield 2.1 g (37% yield) of dried particles.

Example 11 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (11)

0.52 g of the CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole and 37.3 g of 4-methyl-2-pentanone (MIBK) were obtained. Synthesized from The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 3.5 g (0.02 equiv) of DER ™ 332 (product of Dow Chemical) and 3.5 g MIBK was added dropwise over 15 minutes, then the reaction was stirred at 1000 rpm for 1 hour under argon atmosphere, then 3 g Heptane was added dropwise over 1 hour. The reaction was stirred at 1000 ppm for 4 hours. A milky white dispersion formed. The dispersion was drained, centrifuged, washed with MIBK and evaporated to dryness to yield 3.0 g (53% yield) of dried particles.

Example 12. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (12)

Unencapsulated core particles 12 were prepared from Example 1 from 1.05 g of CTBN-epoxy adduct from Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ™ 332 and 51 g of MIBK. It synthesize | combined using the process of. The reaction was stirred at 1000 rpm for 6 hours to yield 4.4 g (71% yield) of particles.

Example 13. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (13)

0.52 g CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole in a three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropwise funnel and argon gas inlet , Heptane 5.1 g, 4-methyl-2-pentanone (MIBK) 42.3 g were charged. The reaction flask was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 3.5 g (0.02 equiv) of DER ^™ 332 (Dow Chemical) and 3.6 g of MIBK was added dropwise over 15 minutes, then the reaction was stirred at 1000 rpm for 6 hours. A milky white dispersion formed. The dispersion was drained, centrifuged, washed with MIBK and evaporated to dryness to yield 3.4 g (60% yield) of particles.

Example 14 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and “Purified” HyPox ^™ RK 84 (14)

0.52 g CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole in a three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropwise funnel and argon gas inlet , 5.1 g heptane and 46.8 g 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath, purged with argon and stirred at 300 rpm for 1 hour. A solution of 3.5 g (0.02 equiv) of DER ^™ 332 (Dow Chemical) and 3.5 g of MIBK was added dropwise over 15 minutes, and then the reaction was stirred at 300 rpm for 1 hour and then at 1000 rpm for an additional 5 hours. A milky white dispersion formed. The dispersion was drained, centrifuged, washed with MIBK and evaporated to dryness to afford 3.2 g (57% yield) of particles.

Example 15 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (15)

Unencapsulated core particles 15 were 0.51 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^™ 332, 15.3 g of heptane and 34 g of MIBK Synthesized using the process of Example 13. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere to yield 4.5 g (80% yield) of particles.

Example 16 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (16)

Unencapsulated core particles 16 were 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^™ 332, 2.6 g of heptane and 49 g of MIBK Was synthesized using the process of Example 13 from, and the reaction was stirred at 1000 rpm for 6 hours under argon atmosphere to yield 2.4 g (42.4% yield) of particles.

Example 17. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (17)

Unencapsulated core particles 17 consisted of 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^™ 332, 10.2 g of heptane and 41 g of MIBK Synthesized using the process of Example 13. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere to yield 3.9 g (69% yield) of particles.

Example 18 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA, and HyPox ™ RK 84 (18)

0.52 g CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole in a three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropwise funnel and argon gas inlet And 47.3 g of 4-methyl-2-pentanone (MIBK). The reactor was placed in an 80 ° C. bath and purged with argon. After the reaction was stirred at 300 rpm for 1 hour, a solution of 3.5 g (0.02 equiv) of DER ^™ 332 (Dow Chemical) and 3.5 g of MIBK was added dropwise over 15 minutes, followed by reaction at 300 rpm for 1 hour and then 1000 rpm Stirred for an additional 5 h. A milky white dispersion formed. The dispersion was drained, centrifuged, washed with MIBK and evaporated to dryness to yield 4.53 g (80% yield) of particles.

Example 19. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (19)

Unencapsulated core particles 19 were obtained from Example 13 from 0.51 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^™ 332 and 51 g of MIBK. Synthesis was carried out using the process of and the reaction was stirred at 1500 rpm for 6 hours under an argon atmosphere to yield 4.05 g (71.5% yield) of particles.

Example 20 Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (20)

Unencapsulated core particles 20 consisted of 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^™ 332, 7.6 g of heptane and 43 g of MIBK Was synthesized using the process of Example 13 from, and the reaction was stirred at 1000 rpm for 6 hours to yield 4.05 g (71.5% yield) of particles.

Example 21.Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (21)

The unencapsulated core particles 21 were 0.51 g of the CTBN-epoxy adduct of Example 2, 1.65 g (0.02 mol) of 2-methylimidazole, 3.5 g (0.02 equiv) of DER ^TM 332, 7.6 g of heptane and 43 g of MIBK. Synthesized using the process of Example 13. The reaction was stirred at 1000 rpm for 16 hours to yield 3.6 g (64% yield) of particles.

Example 22. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (22)

Unencapsulated core particles 22 were 0.51 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.85 g (0.022 equivalents) of DER ^™ 332, 7.6 g of heptane and 43 g of MIBK. Synthesized using the process of Example 13. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere to yield 4.95 g (82.3% yield) of particles. Droplets of the dispersion were diluted with MIBK, coated on a glass slide and dried at room temperature under vacuum. The dried sample was sputtered with a thin gold layer and its electron micrographs (FIGS. 1 and 2) were taken with a Hitachi S-2460N scanning electron microscope.

Example 23. Synthesis of Unencapsulated Core Particles from 2-Methylimidazole, DGEBA and HyPox ™ RK 84 (23)

The unencapsulated core particles 23 consisted of 0.51 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.85 g (0.022 equiv) of DER ^TM 332, 7.6 g of heptane and 42 g of MIBK Synthesized using the process of Example 13. The reaction was stirred at 1000 rpm for 16 hours to yield 4.49 g (74.7% yield) of particles.

Encapsulation Examples of Unencapsulated Core Particles

Example 24. Synthesis of Encapsulated Particles from 2-Methylimidazole, DGEBA, HyPox ™ RK 84 and MDI (24)

The microcapsule core was prepared from Example 2 from 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.85 g (0.022 equiv) of DER ^™ 332, 7.6 g of heptane and 42 g of MIBK. Synthesis using process. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere. Droplets of the dispersion were removed, diluted with MIBK, coated on a glass slide, and dried at room temperature under vacuum. The dried sample was sputtered with a thin gold layer, and electron micrographs were taken with a Hitachi S-2460N scanning electron microscope. Encapsulation is initiated by the dropwise addition of 1.56 g (0.0125 equivalents) of 4,4'-methylenebis (phenyl isocyanate) (most commonly referred to as MDI) and a 14.1 g solution of MIBK over 110 minutes, followed by reaction at 15 rpm at 15 rpm. Stir under argon atmosphere for hours. Droplets of the dispersion were dried and its FT-IR spectrum showed complete conversion of isocyanate residues. After confirming that all isocyanates have been consumed, the dispersion droplets are removed, diluted with additional MIBK, coated on glass slides and dried at room temperature under vacuum. The dried sample was sputtered with a thin gold layer and its electron micrographs were taken with a Hitachi S-2460N scanning electron microscope (FIGS. 3 and 4).

Example 25. 2-methylimidazole, DGEBA, Hypox ^™ Synthesis of Microcapsules from RK 84, MDI and 4,4'-methylenebis (N, N-diglycidylaniline)

The microcapsule core is 0.51 g of the CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methyleneimidazole, DER ^™ 3.332 g (0.022 eq) of 332, 7.6 g of heptane and 42 g of MIBK were synthesized using the process of Example 13 and the reaction was stirred at 1000 rpm for 6 hours under argon atmosphere. Encapsulation is initiated by dropwise addition of a solution of 1.4 g (0.0112 equivalents) of MDI, 0.16 g (0.00038 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 14.1 g of MIBK over 110 minutes, The reaction was then stirred at 1000 rpm for 15 hours under argon atmosphere. Droplets of the dispersion were dried and its FT-IR spectrum showed complete conversion of isocyanate residues.

Example 26. Synthesis of Microcapsules from 2-methylimidazole, DGEBA, HyPOx ^™ RK 84 and MDI (26)

The microcapsule core was prepared from Example 2 from 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.86 g (0.022 equiv) of DER ^™ 332, 7.6 g of heptane and 42 g of MIBK. Synthesis using process. The reaction was stirred at 1000 rpm for 6 hours under argon atmosphere. A solution of 1.57 g (0.0125 equiv) MDI and 14.1 g MIBK was added dropwise over 90 minutes, and the reaction was then stirred under an argon atmosphere for 15 hours at 1000 rpm. Droplets of the dispersion were dried and its FT-IR spectrum showed complete conversion of isocyanate residues.

Example 27 Synthesis of Microcapsules from 2-methylimidazole, DGEBA, Hypox ^™ RK 84, MDI, and 4,4′-methylenebis (N, N-diglycidylaniline)

The microcapsule core was prepared from Example 2 from 0.52 g of CTBN-epoxy adduct of Example 2, 1.64 g (0.02 mol) of 2-methylimidazole, 3.85 g (0.022 equiv) of DER ^™ 332, 7.6 g of heptane and 43 g of MIBK. Synthesized using the process, and the reaction was stirred at 1000 rpm for 6 hours under argon atmosphere. Encapsulation consists of a solution of 2.8 g (0.0223 equivalents) of MDI (Sigma Aldrich), 0.35 g (0.0033 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 14.1 g of MIBK. Start by dropwise over 240 minutes, then the reaction was stirred at 1000 rpm for 15 hours under argon atmosphere.

Example 28 Synthesis of Microcapsules from 2-methylimidazole, DGEBA, Hypox ^™ RK 84, MDI, and 4,4′-methylenebis (N, N-diglycidylaniline)

In a three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropwise funnel and argon gas inlet, 1.03 g of the CTBN-epoxy adduct of Example 2, 3.28 g (0.04 mol) of 2-methylimidazole ), 15.2 g of heptane and 76 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 h, a solution of 7.7 g (0.044 equiv) of DER ^™ 332 (Dow Chemical) and 7.7 g of MIBK was added dropwise over 40 minutes, and the reaction was then stirred under an argon atmosphere for 6 hours at 1000 rpm. A milky white dispersion formed. Droplets of the dispersion were diluted, coated on a glass slide and dried at room temperature in a vacuum oven. The dried sample was sputtered into a thin Au layer and photographed by scanning electron microscopy. Encapsulation is initiated by dropwise addition of a solution of 2.8 g (0.0223 equiv) of MDI, 0.32 g (0.003 equiv) of 4,4'-methylenebis (N, N-diglycidylaniline) and 28.2 g of MIBK over 240 minutes, The reaction was then stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Example 29. Synthesis of microcapsules from 2-methylimidazole, DGEBA, HyPox ™ RK 84L, Desmodur® W and 4,4'-methylenebis (N, N-diglycidylaniline)

In a three neck round bottom flask equipped with PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet, 2.09 g of CTBN-epoxy adduct of Example 2, 6.56 g (0.08 mol) of 2-methyl Imidazole and 183 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 15.4 g (0.088 eq) of DER ^TM 332 (Diglycidyl ether of Dow Chemical A (DGEBA)) and 18.7 g of MIBK was added dropwise over 1 hour, after which the reaction was carried out at 1000 rpm. Stir under argon atmosphere for 6 hours. A milky white dispersion formed. The particles were allowed to settle under gravity to allow the supernatant liquid to be decanted. The particles were redispersed in MIBK. The remaining dispersion was filtered through a small pore size membrane filter. The particles were redispersed in MIBK and then filtered through a 30 μm pore size filter to remove large particles and aggregates. A few droplets of the resulting dispersion were dried, sputtered with gold and loaded onto the SEM. Its photomicrographs showed that the particles were of a quality that was acceptable to allow them to proceed to the encapsulation step. The solids content of the dispersion was measured at 9.84% (w / w). The yield of the total dispersion was 84.4 g.

A three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet was charged with 0.83 g of CTBN-epoxy adduct of Example 2, 10.3 g of MIBK and purified dispersion. I was. The reactor was placed in an 80 ° C. bath and purged with argon. 17 g of heptane was added dropwise thereto over 1 hour. Encapsulation weighs 1.9 g (0.0145 equivalents) of Desmodur® W (liquid alicyclic diisocyanate from Bayer MaterialScience), 0.19 g (0.002 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 g of MIBK The solution was initiated dropwise over 4 hours, after which the reaction was stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Example 30 (precursor). Synthesis of Microcapsules Comprising Two Shell Materials

In a three-neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet, 2.09 g of the CTBN-epoxy adduct of Example 2, 6.56 g (0.08 mol) of 2-methyl Midazole and 183 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 15.4 g (0.088 equiv) of DER ^™ 332 (available from Dow Chemical) and 18.7 g of MIBK was added dropwise for 1 hour, then the reaction was stirred at 1000 rpm for 6 hours under an argon atmosphere. A milky white dispersion formed. The particles were allowed to settle under gravity to allow the supernatant liquid to be decanted off. The particles were redispersed in MIBK. The remaining dispersion was filtered through a small pore size membrane filter. The particles were redispersed in MIBK and then filtered through a 30 μm pore size filter to remove large particles and aggregates.

A three necked round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet was charged with 0.83 g of Example 2 CTBN-epoxy adduct, 10.3 g of MIBK and purified dispersion. . The reactor was placed in an 80 ° C. bath and purged with argon. 17 g of heptane was added dropwise thereto over 1 hour. Encapsulation with the first shell layer weighs 1.9 g (0.0145 equivalents) of Desmodur® A solution of W (by Bayer Material Science), 0.19 g (0.002 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 g of MIBK was added dropwise over 4 hours The reaction was then stirred at 1000 rpm for 12.5 hours under argon atmosphere.

The second shell layer is 1.9 g (0.0145 equiv) of Desmodur® W (by Bayer Material Science), 0.19 g (0.002 equiv) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 A solution of g of MIBK was formed dropwise over 4 hours, after which the reaction was stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Example 31 (Precursor), Synthesis of Microcapsules Comprising Two Shell Materials, with the Outer Shell Material Made of Epoxy-Compatible Materials

In a three neck round bottom flask equipped with PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet, 2.09 g of CTBN-epoxy adduct of Example 2, 6.56 g (0.08 mol) of 2-methyl Imidazole and 183 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 15.4 g (0.088 equiv) of DER ^™ 332 (available from Dow Chemical) and 18.7 g of MIBK was added dropwise over 1 hour, and then the reaction was stirred at 1000 rpm under an argon atmosphere for 6 hours. A milky white dispersion formed. The particles were allowed to settle under gravity to allow the supernatant liquid to be decanted off. The particles were redispersed in MIBK. The remaining dispersion was filtered through a small pore size membrane filter. The particles were redispersed in MIBK and then filtered through a 30 μm pore size filter to remove large particles and aggregates.

A three necked round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet was charged with 0.83 g of Example 2 CTBN-epoxy adduct, 10.3 g of MIBK and purified dispersion. . The reactor was placed in an 80 ° C. bath and purged with argon. 17 g of heptane was added dropwise thereto over 1 hour. The first shell layer encapsulation weighs 1.9 g (0.0145 equivalents) of Desmodur® A solution of W (by Bayer Material Science), 0.19 g (0.002 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 g of MIBK was added dropwise over 4 hours The reaction was then stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Second shell layer weighs 1.9 g (0.0145 equivalents) of Desmodur® W (by Bayer MaterialScience), 1.9 g CVC Thermoset Materials HyPox ^TM A solution of RA1340 and 18.9 g of MIBK was added dropwise over 4 hours, after which the reaction was stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Example 32 (Precursor), Synthesis of Microcapsules Comprising Two Shell Materials, with the Outer Shell Material Made of an Epoxy-Compatible Material

In a three neck round bottom flask equipped with PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet, 2.09 g of CTBN-epoxy adduct of Example 2, 6.56 g (0.08 mol) of 2-methyl Imidazole and 183 g of 4-methyl-2-pentanone (MIBK) were charged. The reactor was placed in an 80 ° C. bath and purged with argon. After 1 hour, a solution of 15.4 g (0.088 equiv) of DER ^™ 332 (available from Dow Chemical) and 18.7 g of MIBK was added dropwise over 1 hour, and then the reaction was stirred at 1000 rpm for 6 hours under argon atmosphere. A milky white dispersion formed. The particles were allowed to settle under gravity to allow the supernatant liquid to be decanted off. The particles were redispersed in MIBK. The remaining dispersion was filtered through a small pore size membrane filter. The particles were redispersed in MIBK and then filtered through a 30 μm pore size filter to remove large particles and aggregates.

A three neck round bottom flask equipped with a PTFE fluoropolymer half moon overhead stirrer, reflux condenser, dropping funnel and argon gas inlet was charged with 0.83 g of CTBN-epoxy adduct of Example 2, 10.3 g of MIBK and purified dispersion. I was. The reactor was placed in an 80 ° C. bath and purged with argon. 17 g of heptane was added dropwise thereto over 1 hour. Encapsulation weighs 1.9 g (0.0145 equivalents) of Desmodur® A solution of W (by Bayer Material Science), 0.19 g (0.002 equivalents) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 g of MIBK was added dropwise over 4 hours The reaction was then stirred at 1000 rpm for 12.5 hours under argon atmosphere.

The second shell layer added dropwise 1.9 g (0.0145 equiv) of Desmodur17 g heptane over 1 hour. W (by Bayer Material Science), 1.9 g of Toagosei GP-301 graft polyacrylate, 0.19 g (0.002 equivalent) of 4,4'-methylenebis (N, N-diglycidylaniline) and 18.9 g A solution of MIBK was formed dropwise over 4 hours, after which the reaction was stirred at 1000 rpm for 12.5 hours under argon atmosphere.

Preparation Examples of Masterbatches:

Example 33 Preparation of a Masterbatch from the Particles of Example 24

The dispersion of the particles of Example 24 was evaporated in vacuo at 50 ° C. to give a yellow solid, ground in a mortar and in a ratio of particles to epoxy resin 35:65 (w / w) in diglycidyl ether of bisphenol A. Added. The mixture was dispersed for 20 minutes using a 3-roll mill to give a creamy yellow dispersion.

Example 34 Preparation of a Masterbatch from the Particles of Example 28

At room temperature, 10 g of diglycidyl ether of bisphenol A was added to the reaction mixture of Example 28 containing a dispersion of particles and stirred for 3 hours. The solvent was removed under vacuum at 31 ° C. with a solids content of 86% (w / w). From this, 12.86 g were removed and mixed with an additional 7.90 g of diglycidyl ether of bisphenol A. The mixture was then treated for an additional 3 minutes using a 3-roll mill to yield a creamy yellow dispersion.

Performance result:

For solvent resistance testing, the mixture was prepared by combining particles, diglycidyl ether of bisphenol A and MIBK in a ratio of 4:50:46 (w / w). The mixture was then placed in a 40 ° C. oil bath and visually monitored for viscosity changes. The results are shown in Table 1 below. An aliquot of the mixture was coated on a glass slide as a thin film and dried under vacuum at room temperature. DSC traces were obtained using a TA instrument Q10 Differential Scanning Calorimeter using a temperature window of 30 to 250 ° C., heating rate 5 ° C./min and performed under nitrogen atmosphere. The results are shown in Table 1 below.

Solvent resistance and DSC results of unencapsulated and encapsulated particles Solvent resistance and DSC results of unencapsulated and encapsulated particles particle Unencapsulated / Encapsulated Content-based DSC Gel time (h) T _max (heating, ℃) H (J / g) 22 Not encapsulated 14 105 297 24 Encapsulated 120 119 330 25 Encapsulated 170 124 307 27 Encapsulated 240 142 200 28 Encapsulated 190 124 218

The present invention has been described in detail with reference to specific embodiments thereof, and it is apparent to those skilled in the art that many variations and modifications are possible without departing from the spirit and scope of the following claims.

Claims (19)

(a) amines,
(b) epoxy resins and
(c) elastomer-epoxy adducts
Curing agent for epoxy resin, consisting of the reaction product of. The method of claim 1 wherein the curing agent is
(a) amines,
(b) epoxy resins and
(c) carboxyl-terminated butadiene-acrylonitrile (CTBN) -epoxy adduct
A curing agent comprising the reaction product of. The curing agent of claim 2, wherein the nitrile content of the CTBN is about 12-35 weight percent. The curing agent of claim 2, wherein the curing agent is formed as a core phase of the dispersion and the particles are encapsulated into a polymer shell. The curing agent of claim 4, wherein at least two polymer shells are formed in a step-wise fashion by reacting the particles with polyfunctional isocyanates. The curing agent of claim 4, wherein at least two polymer shells are formed in a stepwise manner by reacting the particles with a polyfunctional isocyanate and a polyfunctional epoxy compound. The curing agent of claim 4, wherein at least two polymer shells are formed in a stepwise manner by reacting the particles with a polyfunctional isocyanate and a polyfunctional epoxy compatible compound. The curing agent of claim 4, wherein at least two polymer shells are formed in a stepwise manner by reacting the particles with a polyfunctional isocyanate, a polyfunctional epoxy compound and an epoxy compatible compound. As a composition containing an epoxy resin and a curing agent,
The curing agent
(a) amines,
(b) epoxy resins and
(c) elastomer-epoxy adducts
Composition, the reaction product of which is The method of claim 9, wherein the curing agent
(a) amines,
(b) epoxy resins and
(c) carboxyl-terminated butadiene-acrylonitrile (CTBN) -epoxy adduct
Composition, the reaction product of which is The composition of claim 10, wherein the nitrile content of the CTBN is about 12-35 weight percent. An electronic component attached to a substrate by an epoxy adhesive,
On the epoxy adhesive
(a) amines,
(b) epoxy resins and
(c) elastomer-epoxy adducts
An electronic component comprising a curing agent composed of a reaction product of. The electronic component of claim 12, wherein the electronic component forms part of a circuit board. The electronic component of claim 12, wherein the electronic component is an integrated circuit chip mounted on a substrate with the epoxy adhesive. The electronic component according to claim 12, wherein the electronic component is a semiconductor device attached to a substrate with an epoxy adhesive. A fixed array ACF comprising gold particles dispersed in a predetermined pattern in an adhesive film comprising an epoxy adhesive and a curing agent,
Wherein the curing agent is the reaction product of an amine, an epoxy resin and an elastomer-epoxy adduct. The composition of claim 16 wherein the composition is formulated to be useful as a high Tg one-part molding compound comprising a protected phenolic compound, wherein the protected phenolic compound comprises an aryl glycidyl carbonate moiety. ACF. 18. The ACF of claim 17, wherein the composition is formulated to be useful as a sheet molding compound (SMC), bulk molding compound (BMC) or dough molding compound (DMC). The electronic component of claim 12, wherein the electronic component forms an electronic display.

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