Poly -ethylene-vinyl acetate copolymer blends

Bicontinuous controlled-release matrices, poly(DL-lactic acid)-ethylene-vinyl acetate copolymer blends, 182-192... 

Poly(ethylene vinyl acetate) copolymers are commonly used in the wire and cable jacket compounds because of easy processing and good compatibility with many traditional flame retardants such as ATH and MDH. Recently, EVA also demonstrated their ability to promote nanocomposite formation by melt-blending with organoclays [38, 39]. 

Fuhrer MS, Nygard J, Shih L, Forero M, Yoon Y-G, Mazzoni MSC, Choi HJ, Ihm J, Louie SG, Zettl A, McEuen PL (2000) Crossed nanotube junctions. Science 288 494 Gelves GA, Lin B, Sundararaj U, Haber JA (2006) Low electrical percolation threshold of sUvct and copper nanowires in polystyrene composites. Adv Funct Mater 16 2423 Gkourmpis T, Svanberg C, Kahappan SK, Schaffer W, Obadal M, Kandiollcu G, Tranchida D (2013) Improved electrical and flow properties of conductive polyolefin blends modificatirai of poly(ethylene vinyl acetate) copolymer/carlxHi black with ethylate—propylene copolymer. Eur Polym 149 1975... 

Bicontinuous Controlled-Release Matrices Composed of Poly(D,L-lactic acid) Blended with Ethylene—Vinyl Acetate Copolymer... 

As reported by Diehl et al. [58], interpolymers are also compatible with a broader range of polymers, including styrene block copolymers [59], poly(vinyl chloride) (PVC)-based polymers [60], poly(phenylene ethers) [61] and olefinic polymers such as ethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer and chlorinated polyethylene. Owing to their unique molecular structure, specific ESI have been demonstrated as effective blend compatibilizers for polystyrene-polyethylene blends [62,63]. The development of the miscibility/ compatibility behavior of ESI-ESI blends differing in styrene content will be highlighted below. 

Burt HM, Jackson JK, Bains SK, Liggins RT, Oktaba AM, Arsenault AL, Hunter WL. Controlled delivery of taxol from microspheres composed of a blend of ethylene-vinyl acetate copolymer and poly (d,l-lactic acid). Cancer Lett 1995 88 73-79. 

CH1 Cheng, S.-K. and Chen, C.-Y., Study on the phase behavior of ethylene-vinyl acetate copolymer and poly(methyl methacrylate) blends by in situ polymerization, J. Appl. 

Aside from process comparisons, the main contrast between the systems is that of size, weight, and cost, especially for pressurized systems. Construction of batch reactors for use with ethylene at pressures of 1000 psi (70 atm) and upward has to be massive. The simple construction of the Loop process just pumps and pipework blends itself to use at high pressures. Apart from cost and weight, the small volume of the Loop reactor has obvious safety advantages. Despite these attractions, the Loop reactor system has so far been used successfully only for low-pressure systems such as poly(vinyl acetate) homopolymer for adhesives and copolymers for paint. Large-scale production of ethylene-vinyl acetate copolymers has yet to be demonstrated. 

Dalai, S., Wenxiu, G., Radiation effects on poly(propylene) (PP)/ethylene-vinyl acetate copolymer (EVA) blends. Journal of Applied Polymer Science 2002, 86, 3420-3424. 

R. P. Fellmann, W. H. Stass, and D. R. Kory, Impact-Resistant Polymer Mass, Ger. Offen. 2,748,751 (1978). Interpenetrating networks with poly(Me methacrylate). Co-continuous interpenetrating networks of chains. Ethylene vinyl acetate copolymer/poly(Me methacrylate) blends. 

Various workers have discussed aspects other than those mentioned above in studies of the viscoelastic properties of polymers. These include PVOH [62], hydroxy-terminated polybutadiene [63], styrene-butadiene and neoprene-type blends [64], and polyamidoimides [65]. Other aspects of viscoelasticity that have been studied include relaxation phenomena in PP [66] and methylmethacrylate-N-methyl glutarimide copolymers [67], shear flow of high-density polyethylene [68], Tg of PMMA and its copolymers with N-substituted maleimide [69] and ethylene-vinyl acetate copolymers [70], and creep behaviour of poly(p-phenylene terephthalate) [71] and PE [72]. 

Two-component systems have received some attention. - Poly(vinyl-idene fluoride>-poly(methyl or ethyl methacrylate)s blends have been mentioned in the previous section. A study of compatibility in blends of poly(vinyl chloride) and ethylene-vinyl acetate copolymer (EVA) has been reported. Spin-lattice relaxation time measurements were bi-exponential corresponding to rigid [poly(vinyl chloride)] and mobile (EVA) phases. A precipitated mixture showed intermingling of EVA in the poly(vinyl chloride) phase, but phase separation occurred on heating. Cashell et a/. have contributed a short note on the effects of magnetic susceptibility inhomogeneities of lincwidths in carbon black-filled... 

The determination of the experimental variables for apphcation of this approach is based on analysis of FTIR data on the blends and is covered in the references noted above. The application of the association model to determine or predict the phase behavior of interacting polymer systems include poly(2,6-dialkyl-4-vinyl phenol) blends with poly(n-alkyl methacrylates) and ethylene-vinyl acetate copolymers [217], poly(4-vinyl phenol)/poly(hydroxybutyrate) blends [218] and poly(4-vinyl phenol) in ternary blends with PEMA and PMMA [219] as weU as a number of examples in [92]. The determination of the equihbrium constants Ka and Kb) from FTIR data has been reported for ethylene-methacryhc add copolymers with polyethers [118] and ethylene-methacrylic add copolymers with poly(2-vinyl pyridine) [220]. 

Some specific recent applications of the GC-MS technique to various types of polymers include the following PE [49,50], poly(l-octene) [51], poly(l-decene) [51], poly(l-dodecene) [51], 1-octene-l-decene-l-dodecene terpolymer [51], chlorinated polyethylene [52], polyolefins [53, 54], acrylic acid methacrylic acid copolymers [55], polyacrylates [56], styrene-butadiene and other rubbers [57-59], nitrile rubber [60], natural rubbers [61, 62], chlorinated natural rubber [63, 64], polychloroprene [65], PVC [66-68], silicones [69, 70], polycarbonates [71], styrene-isoprene copolymers [72], substituted PS [73], polypropylene carbonate [74], ethylene-vinyl acetate copolymers [75], Nylon [76], polyisopropenyl cyclohexane a-methyl styrene copolymers [77], m-cresol-novolac epoxy resins [78], polymeric flame retardants [79], poly(4-N-alkyl styrenes) [80], polyvinyl pyrrolidone [81], vinyl pyrrolidone-methyl acryloxysilicone copolymers [82], polybutylcyanoacrylate [83], polysulfide copolymers [84], poly(diethyl-2-methacryloxy)ethyl phosphate [85], ethane-carbon monoxide copolymers [86], polyetherimide [87], bisphenol A [88], ethyl styrene [89], styrene-isoprene block copolymer [89], polyvinyl alcohol-co-vinyl acetate [90], epoxide thiol [91], maleic acid-propylene copolymer [92], P-hydroxy butyrate-P-hydroxy valerate copolymer [93], polycaprolactams [39,94], PS [95,96], polypyrrole [95,96], polyhydroxy alkanoates [97], poly(p-chloromethyl) styrene [81], polybenzooxazines and siloxy substituted polyoxadisila-pentanylenes [98,99] poly benzyl methacrylates [100], polyolefin blends after ageing in soil [101] and polystyrene peroxide [43]. 

Figure 5 Debye-Scholte plots for two blends of poly(ethylene/vinyl acetate) [poly(EVA)] and a low molecular weight polyethylene with narrow MWD. The copolymer has a content of 7.5 /o VA and the concentrations of copolymer in the blend...

Conducting polymers that can be molded by conventional melt processes have been made by attaching side groups to the conjugated polymers of Table 11.5. For example, poly(3-octylthiophene) in the undoped state can be molded by compression or injection just like other thermoplastics [14]. When films of this polymer are doped with FeClj, conductivities of over 10 S/cm are measured. Even a blend of 20 parts of the polymer with 80 parts of an ethylene-vinyl acetate copolymer can be doped with iodine to a conductivity of about 1 S/cm. 

Poly(ethyl methacrylate) (PEMA) yields truly compatible blends with poly(vinyl acetate) up to 20% PEMA concentration (133). Synergistic improvement in material properties was observed. Poly(ethylene oxide) forms compatible homogeneous blends with poly(vinyl acetate) (134). The T of the blends and the crystaUizabiUty of the PEO depend on the composition. The miscibility window of poly(vinyl acetate) and its copolymers with alkyl acrylates can be broadened through the incorporation of acryUc acid as a third component (135). A description of compatible and incompatible blends of poly(vinyl acetate) and other copolymers has been compiled (136). Blends of poly(vinyl acetate) copolymers with urethanes can provide improved heat resistance to the product providing reduced creep rates in adhesives used for vinyl laminating (137). 

Three-component polypropylene, 1-99 wt% PP, blends comprised 1. either acidified PP, its mixture with PP, or a mixture of PP with carboxylic acid-modified EPR 2. 99-1 wt% of maleated polymer [e.g., poly(methyl methacrylate-co-styrene-co-MA] and 3. epoxy group-containing copolymer [e.g., 0.1-300 phr of ethylene-methyl methacrylate-glycidyl methacrylate = 65-15-20 or ethylene-vinyl acetate-glycidyl methacrylate = 85-5-10]. The blends were used to mold car bumpers and fenders, with good stiffness and low-temperature impact resistance ... 

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