Resin-modified

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

Dicyclopentadiene is also polymerized with tungsten-based catalysts. Because the polymerization reaction produces heavily cross-Unked resins, the polymers are manufactured in a reaction injection mol ding (RIM) process, in which all catalyst components and resin modifiers are slurried in two batches of the monomer. The first batch contains the catalyst (a mixture of WCl and WOCl, nonylphenol, acetylacetone, additives, and fillers the second batch contains the co-catalyst (a combination of an alkyl aluminum compound and a Lewis base such as ether), antioxidants, and elastomeric fillers (qv) for better moldabihty (50). Mixing two Uquids in a mold results in a rapid polymerization reaction. Its rate is controlled by the ratio between the co-catalyst and the Lewis base. Depending on the catalyst composition, solidification time of the reaction mixture can vary from two seconds to an hour. Similar catalyst systems are used for polymerization of norbomene and for norbomene copolymerization with ethyhdenenorbomene. 

The polymeric encapsulating resin, modified by additives, must possess adequate mechanical strength, adhesion to package components, manufacturing and environmental chemical resistance, electrical resistance, GTE matching, as weU as thermal and moisture resistance in the use-temperature range. 

Long-chain aUphatic acids such as adipic acid (qv) [124-04-9] are generally used to improve flexibiUty and enhance impact properties, demonstrating subtle improvements over resins modified with the ether glycols (diethylene glycol) and polyether glycols (polypropylene glycol) (see PoLYETHERs). 

Miscellaneous Derivatives. Other derivatives of toluene, none of which is estimated to consume more than ca 3000 t (10 gal) of toluene aimuaHy, are mono- and dinitrotoluene hydrogenated to amines ben2otrich1 oride and chlorotoluene, both used as dye intermediates / 7-butylben2oic acid from / 7-butyltoluene, used as a resin modifier dodecyltoluene converted to a ben2yl quaternary ammonium salt for use as a germicide and biphenyl, obtained as by-product during demethylation, used in specialty chemicals. Toluene is also used as a denaturant in specially denatured alcohol (SDA) formulas 2-B and 12-A. 

One approach for ameliorating the highly brittle nature of these cements has involved the use of tougher, more ductile fillers (62,63). Another approach for improving the overall properties of traditional glass—ionomer cements involves the development of hybrid cement-composites and resin-modified cements (64—68). 

Resin-Modified Glass—Ionomer Cements. Resin-modified glass—ionomer cements are based on poly(alkeonic acid) systems that have... 

Resin-modified glass—ionomer lining and restorative materials add a multifunctional acidic monomer to the poly(acryhc acid) [9003-01 Hquid component of the system. Once the glass powder and Hquid are mixed, setting can proceed by the acid—glass—ionomer reaction or the added monomer can be polymerized by a free-radical mechanism to rapidly fix the material in place (74,75). The cured material stiH retains the fluoride releasing capabiHties of a glass—ionomer. 

Most polyesters (qv) are based on phthalates. They are referred to as aromatic-aHphatic or aromatic according to the copolymerized diol. Thus poly(ethylene terephthalate) [25038-59-9] (PET), poly(butyelene terephthalate) [24968-12-5] (PBT), and related polymers are termed aromatic-aHphatic polyester resins, whereas poly(bisphenol A phthalate)s are called aromatic polyester resins or polyarylates PET and PBT resins are the largest volume aromatic-aHphatic products. Other aromatic-aHphatic polyesters (65) include Eastman Kodak s Kodar resin, which is a PET resin modified with isophthalate and dimethylolcyclohexane. Polyarylate resins are lower volume specialty resins for high temperature (HDT) end uses (see HeaT-RESISTANT POLYAffiRS). 

Year Unmodified resins Modified/advanced resins... 

Ethyl Vinyl Ether. The addition of ethanol to acetylene gives ethyl vinyl ether [104-92-2] (351—355). The vapor-phase reaction is generally mn at 1.38—2.07 MPa (13.6—20.4 atm) and temperatures of 160—180°C with alkaline catalysts such as potassium hydroxide and potassium ethoxide. High molecular weight polymers of ethyl vinyl ether are used for pressure-sensitive adhesives, viscosity-index improvers, coatings and films lower molecular weight polymers are plasticizers and resin modifiers. 

Resin-modified Hard Very good Very good Very good (Alphatic, good aromatic, poor) Fair Good Easy... 

The alkyd resins are of value because of their comparatively low cost, durability, flexibility, gloss retention and reasonable heat resistance. Alkyd resins modified with rosin, phenolic resin, epoxy resins and monomers such as styrene are of current commercial importance. 

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. 

Other blow moldings, injection moldings, resin modifier... 

MPP = phenolic resin (PF) modified PP MPRP = phenolic resin modified PRP. 

Chemical resistance is normally achieved by synthetic resin toppings, polymer or resin-modified cementitious toppings or modular (tiled or paver) toppings. 

Thermally nonconductive Polyamides Resin modifier for plastic thrust chamber... 

Urethane alkyds and urethane oils are oil and alkyd resin-modified polyurethanes dissolved in a volatile solvent. Upon application and solvent evaporation, the coating is crosslinked and cured via oxidation by atmospheric oxygen. 

Phenol-formaldehyde reactions, 399, 380 base-catalyzed, 400-402 Phenol-formaldehyde resins, modified, 410-411... 

B.Gapud, M.Shoemake, E.Searcy, MF resins modified with dicyandiamide sorbitol for impregnation of substrates for post-formable decorative laminates, U.S Patent No.6,001,92 (1999). 

These resin-modified glass polyalkenoate cements have both advantages and disadvantages over conventional glass polyalkenoate cements. However, because of their poor translucency they are recommended only as liners or bases. 

A fundamental criticism of the resin-modified glass polyalkenoate cements is that, to some extent, they go against the philosophy of the glass polyalkenoate cement namely, that the freshly mixed material should contain no monomer. Monomers are toxic, and HEMA is no exception. This disadvantage of composite resins is avoided in the glass polyalkenoate cement as the polyacid is pre-polymerized during manufacture, but the same cannot be said of these new materials. For this reason they may lack the biocompatibility of conventional glass polyalkenoate cements. These materials also absorb excessive amounts of water because of the hydrophilic nature of polyHEMA (Nicholson, Anstice McLean, 1992). 

Antonucci, J. M., McKinney, J. E. Stansbury, J. W. (1988). Resin-modified glass-ionomer cement. US Patent Application 160,856. 

Wilson, A. D. (1990). Resin modified glass-ionomer cements. International Journal of Prosthodontics, 3, 425-46. 

Calcium lignosulfonate Phenol-formaldehyde resin modified with fiirfuryl alcohol [1352]... 

Phenol-formaldehyde resins, modified with benzylamine [3]... 

Y. G. Abdullaev, R. G. Aliev, S. M. Akhmedov, S. M. Zejnally, N. A. Mekhtieva, K. A. Salaeva, and L. I. Sulejmanova. Breaking down of oil emulsion— by treating with potassium salt of phenol-formaldehyde resin, modified with benzylamine. Patent SU 1705332-A, 1992. 

Demand for the different classes of polymer additives varies by resin. Modifiers and processing aids rely heavily on PVC while the property extenders are primarily used in non-PVC resins. PVC is by far the largest consuming resin for polymer additives (excluding fillers), accounting for some 80% of the world-wide volume or 60 % in total value. Polyolefins are a distant second accounting for 8% and 17%, respectively [36]. 

S02-cured epoxy resin. Modified epoxy/acrylic resins (1.2 to 1.4% of sand weight) are mixed with organic peroxide (26 to 60% of resin weight), the mixture is blown into the core box and a hardening mechanism similar to the S02 process takes place. 

Current state-of-the-art technology for the production of MIBK involves one-step liquid phase processes in trickle bed reactors at 100-160°C and 1 to 10 MPa utilizing various multifunctional catalysts including Pd, Pt, Ni or Cu supported on, metal oxides, cation exchange resins, modified ZSM5 and other zeolites with lull energy integration (2,3,4). However, the MIBK... 

Itoh et al. [196] determined selenium (IV) in sea and estuarine waters by an anion-exchange resin modified with bismuthiol (II) and diaminonaphthalene fluorophotometry. An Amberlite IRA-400 anion exchange resin was modified by mixing with an aqueous solution of bismuthiol (II) to give 0.2 mmol per g of... 

Illustrative performance properties for a "general purpose polycarbonate," and for the same resin modified with the additive formulations "700" (without PTFE) and "800" (with PTFE) are summarized in Table IV (adapted from reference 32). It is clear that the objective of minimal effect on performance properties has been attained for this system. It is evident that flame retardant effectiveness attained with minimal levels of additive can provide optimum solutions to the problem of decreasing flammability without sacrifice in performance properties. Work documented to date suggests that in depth studies of thermal degradation such as reported for aromatic sulfonates in polycarbonates (28) would be rewarding for other systems. 

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