Blend HDPE/PMMA

The viscosity versus shear rate data for HDPE/PMMA blend were obtained [87] from only a single source [89] and at a solitary temperature of 160°C (Table B3 of pendix B). However, an exhaustive range of 12 compositions including the pure HDPE and pure PMMA polymer were covered. The data were available only in the low-shear-rate range from 0.01 to 1/s. Using a set of 36 data points, the master rheogram shown in Fig. 4.39 was created. 

Figure 4.39 Master curve for HDPE-PMMA blend at 2.16-kg test load condition for MFI using data from Ref. 89. (Reprinted from Ref. 87 with kind permission from Gordon and Breach Publishers, Lausanne, Switzerland.)...

A comparison of the values of reciprocal log[MFI(r, 0yMFI(r, < >2)] at < >2 s 1 has been shown in Table 8.11. It is evident that when the Tg vidues of the individual components of a blend are not too different, the values of reciprocal log[MFl(r, 0)/MFI(r, 1)] can be taken to be approximately constant. Thus, HDPE/PMMA forms the worst case in Table 8.11 due to the largest Tg value differences between the individual components within the blend systems studied. By the same token, PS/PMMA shows an i proximately constant value of reciprocal log[MFI(r, 0)/MFI(7, 1)]. In the linear plots of redprocal log[MFI(r, 0)/ MFl(r, ] versus reciprocal < >2, the maximum deviations due to temperature would be 63q>ected at < >2 = 1. Thus, if reciprocal log[MFI(7, 0)/MFl(r, 1)] remains approximately constant within a temperature range, the linear plots shown in Figs. 8.27-8.31 can be assumed to be temperature invariant within that temperature range and the entire range of < >2. 

This chapter covers fundamental and applied research on polyester/clay nanocomposites (Section 31.2), which includes polyethylene terephthalate (PET), blends of PET and poly(ethylene 2,6-naphthalene dicarboxy-late) (PEN), and unsaturated polyester resins. Section 31.3 deals with polyethylene (PE) and polypropylene (PP)-montmorillonite (MMT) nanocomposites, including blends of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE). Section 31.4 analyzes the fire-retardant properties of nanocomposites made of high impact polystyrene (HIPS), layered clays, and nonhalogenated additives. Section 31.5 discusses the conductive properties of blends of PET/PMMA (poly (methyl methacrylate)) and PET/HDPE combined with several types of carbon... 

Blends of PET/HDPE have been treated previously in the literature [157, 158]. These are immiscible, but the addition of compatibilizers improves the mechanical properties of the blend, such as styrene-ethylene/butylene-styrene (SEBS) and ethylene propylene diene monomer (EPDM) [157], MAH [158], Poly(ethylene-stat-glycidyl metha-crylate)-graft-poly(acrilonitrile-stat-styrene) (EGMA), poly (ethylene acrylic acid), and maleated copolymers of SEBS, HDPE, ethylene-propylene copolymer (EP). The addition of compatibilizers modifies the rheological properties of blends of PET with HDPE, in such a way that increases in viscosity are observed as the component interactions augment. Changes in crystallization of PET were evaluated in blends with Polyphenylene sulfide (PPS), PMMA, HDPE aromatic polyamides, and copolyesters [159]. 

SEM photomicrographs of blend 1 having HDPE as a matrix in which are dispersed the two minor phases (low-Mw polystyrene/low-Mw PMMA) at 2 min (A) and 15 min (B) of mixing time. PS is extracted by cyclohexane. A stable composite droplet morphology is obtained within 2 min of mixing. The white scale bar denotes 1 pm. (From J. Reignier, B. D. Favis, and M.-Cl. Heuzey, Polymer 44,49-59,2003. With permission.)... 

Thermoplastics used to blend with NR include PS, " polyamide 6, ethylene-vinyl acetate (EVA) copolymer, poly(methyl methacrylate) (PMMA), polypropylene (PP), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE) " and high-density polyethylene (HDPE). To improve the properties of TPNR, modified NR is also used. ENR is the most frequently used modified NR. TPNR blends are prepared by blending NR and thermoplastics in various proportions. The role of rubber is to improve the impact strength and ductility of the plastic. Depending on the ratio, materials with a wide range of properties are obtained. The stiffness of the rubber is increased with the incorporation of plastic into the rubber matrix. The mechanical properties of TPNR again depend on the proportions of the rubber and thermoplastic components. The elastic properties of TPNR are considerably... 

FTIR spectroscopy has been applied in the study of polymer blends including Neoprene rubber, chlorosulfonated PE, nitrile rubber, polyvinyl chloride (PVC) containing carbon black and other fillers [86], Nylon 6 inorganic [87], polyhydroxyether sulfone/poly(N-vinyl pyrrolidone) [88], graphite-based low-density polyethylene [89], caprolactone/Nafion blends [90], polybutylene terephthalate/polyamide [91], polyphenylene sulfide/acrylonitrile - butadiene - styrene [92], PMMA/polypyrrol [93], and lower or high performance liquid chromatography (LDPE/HDPE) [94]. 

Random copolymer addition to binary blends involving copolymers with structural units equal or similar to the blend components or with specific interacting groups capable of non-reactive interaction with one of both the blend components comprises another ternary polymer addition approach. An early example involved EPR (ethylene-propylene rubber) addition to HDPE/PP blends, where synergistic impact strength was observed. In some cases, the random copolymers have been compared to block copolymers comprised of the same units. The compatibihzation of LLDPE/PMMA and LLDPE/poly(MMA-co-4-vinyl pyri-dine(4VP)) blends with poly(ethylene-co-methacrylic acid) (EMAA) addition were compared [47]. Modest improvements in LLDPE/PMMA dispersion and strength were observed. The specific acid-base interaction allowed for much larger improvements with EMAA addition to LLDPE/PMMA-CO-4VP blends. 

Reignier, J. and Favis, B.D., Control of the Subinclusion Microstructure in HDPE/PS/PMMA Ternary Blends, Macromolecules, 33, 6998-7008 (2000). 

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