Polyolefins acrylate

Crompton [81] has reported in detail fractional precipitation procedures for various polymers, such as polyolefins, acrylic polymers, PS, PVC, PUR, rubbers, polyarylamide, and various copolymers. Metcalf and Tomlinson [624] have reported fractional precipitation of antioxidants from PE. Separation of low-MW species from the polymer by repeated fractional precipitation [625] is unsatisfactory for routine use because of the time and manipulative skills required. 

Except for metal-polymer coated, polyolefins, acrylics, and phenolics, these Cfs have been rounded to one significant figure from those reported in the 1988 Recommendations. h- The CF for polyolefins is currently subdivided as follows LDPE, 0.18 HDPE, 0.13 PP, 0.02. If polyolefins coverage only involves PP, a minimum CF of 0.05 is used. 

Grafting reaction Reaction of a monomer and a polymer to form a grafted polymer or copolymer Grafting vinyl silanes onto polyolefins for crosslinked polyolefins acrylic acids onto polyolefins for hydrophilicity maleic anhydride onto polyolefins for compatabilization... 

FIGURE 12.53 U.S. production of synthetic fiber staple and tow showing the relative quantities of acrylic fiber produced compared to nylon, polyester, and polyolefin. Acrylic production peaked in the late 1970s. One of the major factors was the decline of the acrylic carpet market, now dominated by nylon. (From Manufactured Fiber Producer Handbook, 1996 Fiber Organon, February 1997, Fiber Economics Bureau, pub.)... 

Chem. Descrip. Trisnonylphenyl phosphite, 0.75% triisopropanolamine Uses Antioxidant, stabilizer for polyolefins, acrylics, adhesives, elastomers, nylon, PC, PU, PS, PVC, coatings, ABS, PET, food-contact polymers Features Hydrolysis-resist. 

Uses UV absorber/stabilizer for coatings, automotive coatings, styrenics, polyolefins, acrylic, unsat. polymers, PVC, PU, polyacetals, PVB, elastomers, other substrates, food pkg. adhesives Features Offers high solubility and desirable balance of props. Reguiatory FDA 21CFR 175.105... 

Hexachlorophene n. (C6HCl30H)2CH2. A white, essentially odorless, free-flowing powder widely used as a bacteriostat in many thermoplastics including vinyls, polyolefins, acrylics, and polystyrene. 

Total oxygen in polyolefin-acrylate copolymers have been determined by neutron activation analysis (NAA) [14]. 

The final part of this book features tactic polymerizations of functional and nonolefinic (ring-opening) monomers— materials for which many aspects of polymer stereochemistry and microstructure control are very different than for simple polyolefins. Acrylate, epoxide, and lactide polymerizations are addressed in this part, along with tactic olefin/carbon monoxide co- and terpoly-mers. These final chapters provide an expanded view of polymer microstructures and stereocontrol strategies, such as enantiomer-selective polymerization, that may be less familiar to the polyolefin-minded chemist and serve to enhance the reader s overall understanding of stereoregular polymers and polymerization. 

Focuses on industrial polymers classified as polyolefins, acrylics, vinyl polymers, polyesters, polyamides, formaldehyde resins, ether polymers, cellulosics, and silicones... 

Polyester Nylon or polyamide Polyolefin Acrylic Modacrylic... 

A large number of hindered phenoHc antioxidants are based on the Michael addition of 2,6-di-/ f2 -butylphenol and methyl acrylate under basic catalysis to yield the hydrocinnamate which is a basic building block used in the production of octadecyl 3-(3,5-di-/ f2 butyl-4-hydroxyphenyl)propionate, [2082-79-3], tetrakis(methylene-3(3,5-di-/ f2 butyl-4-hydroxylphenyl)propionate)methane [6683-19-8], and many others (63,64). These hindered phenolic antioxidants are the most widely used primary stabilizers in the world and are used in polyolefins, synthetic and natural mbber, styrenics, vinyl polymers, and engineering resins. 2,6-Di-/ f2 -butylphenol is converted to a methylene isocyanate which is trimerized to a triazine derivative... 

If polypropylene is too hard for the purpose envisaged, then the user should consider, progressively, polyethylene, ethylene-vinyl acetate and plasticised PVC. If more rubberiness is required, then a vulcanising rubber such as natural rubber or SBR or a thermoplastic polyolefin elastomer may be considered. If the material requires to be rubbery and oil and/or heat resistant, vulcanising rubbers such as the polychloroprenes, nitrile rubbers, acrylic rubbers or hydrin rubbers or a thermoplastic elastomer such as a thermoplastic polyester elastomer, thermoplastic polyurethane elastomer or thermoplastic polyamide elastomer may be considered. Where it is important that the elastomer remain rubbery at very low temperatures, then NR, SBR, BR or TPO rubbers may be considered where oil resistance is not a consideration. If, however, oil resistance is important, a polypropylene oxide or hydrin rubber may be preferred. Where a wide temperature service range is paramount, a silicone rubber may be indicated. The selection of rubbery materials has been dealt with by the author elsewhere. ... 

Among the different pressure sensitive adhesives, acrylates are unique because they are one of the few materials that can be synthesized to be inherently tacky. Indeed, polyvinylethers, some amorphous polyolefins, and some ethylene-vinyl acetate copolymers are the only other polymers that share this unique property. Because of the access to a wide range of commercial monomers, their relatively low cost, and their ease of polymerization, acrylates have become the dominant single component pressure sensitive adhesive materials used in the industry. Other PSAs, such as those based on natural rubber or synthetic block copolymers with rubbery midblock require compounding of the elastomer with low molecular weight additives such as tackifiers, oils, and/or plasticizers. The absence of these low molecular weight additives can have some desirable advantages, such as ... 

These results demonstrate some interesting chemical principles of the use of acrylic adhesives. They stick to a broad range of substrates, with some notable exceptions. One of these is galvanized steel, a chemically active substrate which can interact with the adhesive and inhibit cure. Another is Noryl , a blend of polystyrene and polyphenylene oxide. It contains phenol groups that are known polymerization inhibitors. Highly non-polar substrates such as polyolefins and silicones are difficult to bond with any technology, but as we shall see, the initiator can play a big role in acrylic adhesion to polyolefins. 

Operating conditions are important determinants of the choice of fabric. Some fabrics (e.g., polyolefins, nylons, acrylics, polyesters) are useful only at relatively low temperatures of 95 to 150°C (200 to 300°F). For high-temperature flue gas streams, more thermally stable fabrics such as fiberglass. Teflon, or Nomex must be used. 

A long-standing goal in polyolefins is the synthesis of polymers bearing polar functional groups such as acrylate, esters, or vinyl ethers, etc [24,40]. These copolymers might endow polyolefins with useful properties such as adhesiveness, dyeability, paintability, and print-ibility. Advances have recently been made in polymerizing polar monomers with cationic metallocene catalysts... 

Since 2-hydroxy-4-alkoxybenzophenones are widely used to stabilize polystyrene, flexible and rigid PVC, celluloses, acrylics, and polyolefins such as PE and PP, the polymeric UV stabilizers shown in Table 1 are used with polystyrene, polymethylmethacrylate, and cellulose triacetate (CTA). The polymeric-HALS are used in polyolefins. 

Blends based on polyolefins have been compatibilized by reactive extrusion where functionalized polyolefins are used to form copolymers that bridge the phases. Maleic anhydride modified polyolefins and acrylic acid modified polyolefins are the commonly used modified polymers used as the compatibilizer in polyolefin-polyamide systems. The chemical reaction involved in the formation of block copolymers by the reaction of the amine end group on nylon and anhydride groups or carboxylic groups on modified polyolefins is shown in Scheme 1. 

Radical induced grafting may be carried out in solution, in the melt phase,292 29 or as a solid state process.296 This section will focus on melt phase grafting to polyolefin substrates but many of the considerations are generic. The direct grafting of monomers onto polymers, in particular polyolefins, in the melt phase by reactive extrusion has been widely studied. Most recently, the subject has been reviewed by Moad1 9 and by Russell.292 More details on reactive extrusion as a technique can be found in volumes edited by Xanthos," A1 Malaika and Baker et a 21 7 The process most often involves combining a frcc-radical initiator (most commonly a peroxide) and a monomer or macromonomer with the polyolefin as they are conveyed through the extruder. Monomers commonly used in this context include MAII (Section 7.6.4.1), maleimidc derivatives and malcate esters (Section 7.6.4.2), (meth)acrylic acid and (meth)acrylate esters (Section 7.6.43), S, AMS and derivatives (Section 7.6.4.4), vinylsilancs (Section 7.6.4.5) and vinyl oxazolines (Section 7.6.4.6). 

Various (meth)acrylic monomers have been successfully grafted onto polyolefins. Most studies deal with functional monomers. Grafting yields obtained with PP are usually low (<20%) and are dependent on the particular monomer. Liu et al.jM carried out a comparative study on the grafting of various functional methacrylates onto PP. The experiments were performed in a batch mixer at 180 °C with 7 wt% monomer and 0.05 wt% 22 as an initiator. Grafting levels (wt%) obtained under these conditions were as follows HPMA (I), TBAEMA (1), GMA (0.8), IIEMA (0.4), DMAEMA (0.3), 32 (0.2). Grafting yields to PE appear generally higher. 

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