Meth acrylate graft polyolefins

and less often MAA or itaconic acid have been successfully grafted onto polyolefins. In the case of AA, grafting is often accompanied by homopolymerization, 

Many studies on the melt phase grafting of GMA onto polyolefins PP 298.3 x5.30i,334.343-347 gpM3 LLDPE, HOPE ) have 

A1 Malaika et have reported on the grafting of antioxidant moieties 

In another study, the monoacrylate 35 was grafted onto PP in the presence of tris(acryIoyhnethyl)propane (36) as coagent.Again close to 100% grafting yield was obtained. This was so despite the fact that 35 was anticipated to be an inhibitor of free radical reactions (in fact, phenols are poor inhibitors of (meth)acrylate polymerization - Section 5.3.4). The tris-acrylatc 36 and related species have previously been used for producing crosslinked/branched xhe structure 

One would not expect this strategy to be useful for grafting onto PE or other polymers less susceptible to shear induced chain scission. 

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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. 

Graft reactions and functionalization reactions Graft copolymer of polystyrene and maleic anhydride graft copolymer of polyolefines and vinylsilanes graft copolymers of polyolefines and (meth)acrylic monomers, graft copolymer of EVA with acrylic acid graft copolymer of polyolefines and maleic anhydride halogenation of polyolefines or EVA... 

Although there are several reports of direct grafting of S onto polyolefins, S and AMS are more often encountered as coagents when grafting MAI I and (meth)acrylic and other monomers. Recent reports describe the use of the functional styrene derivative 38 to attach oxazolinc groups to ABS and to... 

Polyolefin, 100 parts PO [PE, PP, or EPR], was grafted with 0.01-20 parts of the monomers mixture [consisting of 5-50 mol% of glycidyl (meth) acrylate and 95-50 mol% of acrylamide, vinylpyrrolidone, acrylic acid esters, and/or methacrylic acid esters]. Grafted PO was used as modifier for engineering plastics or as adhesion improver for filled plastics ... 

Polyolefin, PO [of ethylene, propylene, butylene, 4-methylpentene, and their copolymers with 1-aUcenes, vinyls, (meth)acrylates - preferably PP], was grafted at a ratio 1 9-4 1 with 1-20 wt% of (meth)acrylic acid and >30 wt% of styrene and/or aUcyl- and/or halo-substituted styrene, methacrylic ester, and 0-60 % of other comonomers [e.g., vinyl aromatic, ester], at least some of the acid units of methacrylic acid and/or acrylic acid bearing a charge and being associated with non-polymeric counterions [e.g., 90 % methyl methacrylate, 5 % butyl acrylate, and 5 % methacrylic acid with either or Mg ". The ionomer could be blended with PO either during or after manufacturing. 

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