ISSN:0032-3888    

DOI:10.1002/pen.760270602

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractBy means of a twin‐roll masticator and Brabender rheometer, the effect of chlorinated polyethylene (CPE) and polyethylene (PE) on the impact strength and processability of poly(vinyl chloride) (PVC) was studied. The experimental results show that CPE can promote the plasticity of PVC and the effect increases with the amount of CPE. Addition of a small amount of PE in PVC/CPE (100/12) makes an impressive improvement in the impact strength of the mixture. The impact strength of PVC/CPE/PE (100/ 12/2.5) at 20°C is 30.0 kJ/m2higher than that of PVC/CPE (100/12). The dynamic viscoelastic spectra, tensile strength, and elongation test reveal that CPE is incompatible with PVC but may act as a compatibilizer for PVC/PE. The disperse state of the polyblend was studied by differential scanning calorimetry (DSC); it was found that the mixing sequence has an influence on the impact strength of the ble

ISSN:0032-3888    

DOI:10.1002/pen.760270603

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe compatibility, morphology, fusion behavior, and mechanical properties of blends of poly(vinyl chloride) (PVC), acrylic resin (ACR), and chlorinated polyethylene (CPE) (100/0–30/0–20) were studied. The experimental results show that the compatibility of the polyblend increases with the amount of ACR added. The blends composed of PVC/ACR/CPE (100/3–25/10–15) are fairly compatible. So far as impact strength is concerned, partially compatible blends are pr

ISSN:0032-3888    

DOI:10.1002/pen.760270604

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe melt rheological behavior of chloro‐polyether and polyepichlorohydrin blends was studied. It was found that both the coupled and uncoupled blends at different blending ratios are pseudoplastic, but there was a great difference in pseudoplastic behavior between them. All the blends obeyed the principles of temperature superposition and composition superposition for plots of shear stress vs. shear rate. A model is proposed to describe and predict the rheological behavior of the blend

ISSN:0032-3888    

DOI:10.1002/pen.760270605

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractMelt blending of a variety of conventional isotropic polymers (both crystalline and amorphous) has shown that considerable reinforcement is obtained from the inclusion of thermotropic liquid crystalline polymers (LCP). When the LCP is a minor component it forms highly elongated domains parallel to the flow direction. The intrinsically high strength and stiffness of the LCP improve the mechanical properties of the resulting blend. This approach is distinguished from the common practice of filling polymers with chopped glass and carbon fibers by the fact that the reinforcing component comes into existenceduringprocessing (molding or extrusion). Many of the problems associated with fibrous fillers are avoided. For example, viscosity of the “in situ composite” is actually lower than that of the base polymer and wear on the compounding and processing equipment is redu

ISSN:0032-3888    

DOI:10.1002/pen.760270606

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe entanglement molecular weight necessary for integrity of processed fiber and film for rigid rod molecular composites is discussed. The case presented is one where the matrix flexible coil polymer has a marginal molecular weight for entanglement. The molecular weight of the rigid rod reinforcement was increased to offset this deficiency. No significant phase separation was observed for solutions undergoing high shear. Steady state shear measurements on rigid rod molecule solutions show that the zero shear viscosity results agree very well with recent theoretical rigid rod molecule behavior predictions.

ISSN:0032-3888    

DOI:10.1002/pen.760270607

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe deformation behavior of miscible amorphous/amorphous PMMA/PEO poly(methyl methacrylate)/poly(ethylene oxide) blends was compared with that of pure PMMA. Small‐angle neutron scattering experiments were performed on labeled systems made of PEO + D‐PMMA + HPMMA. Characteristic molecular parameters such as radius of gyration,Rg, molecular weight,Mw, and interaction parameter,X, were extracted from the coherent scattering cross sections, Molecular anisotropy was measured on the solid state coextruded samples, and the observed drawing efficiency is compared with, the results of shrinkage tests. In the case of PMMA/PEO blends, anomalous scattering behavior precludes any quantitative Interpretation of the scattering patterns, but revealed important structural changes upon drawing, namely a deformation‐induced phase separ

ISSN:0032-3888    

DOI:10.1002/pen.760270608

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe compatibility of polymer blends of high‐molecular‐weight polycarbonate (PC) and high‐molecular‐weight poly(hexamethylene sebacate) (HMS) were characterized. Samples were prepared by solution blending them In methylene chloride followed by doctor blade casting. Optical spectroscopy, tensile stress‐strain, differential scanning calorimetry, and dielectric relaxation spectroscopy were employed to determine the physical and mechanical properties of the blends. These high‐molecular‐weight blends exhibit a limited solubility of HMS In PC as evidenced by a decrease in the glass‐transition temperature of PC. In fact, HMS solubility increases PC mobility sufficiently to allow partial crystallization of PC. Over most of the composition range, HMS phase separates a

ISSN:0032-3888    

DOI:10.1002/pen.760270609

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe thermal and isothermal crystallization behavior of PET/PMMA (poly(ethylene terephthalate)/poly(methyl methacrylate)) alloys was investigated. The crystallization of PET is accelerated significantly by alloying with PMMA. As a result, crystalline specimens could be injection molded with the alloy at low mold temperatures of 19°, 55° and 90°C., whereas a mold temperature of about 130°C is normally required for crystallinity to develop in the virgin PET grade. The impact strength of the alloy specimens increased significantly with decreasing mold temperature despite a comparable degree of crystallinity. The increase in impact strength is correlated to the reduction in the crystallite size and broadening of the crystal size distribution with decreasing mold temperat

ISSN:0032-3888    

DOI:10.1002/pen.760270610

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractAn unusual compatibility was observed with the melt blends of propylene/α‐olefin copolymer with isotactic homopolypropylene. The simple binary blend exhibits a single glass‐transition temperature, and, by differential scanning colorimetry, a single melting and crystallization temperature over the entire blending ratios examined. Depending on the compositions, the characteristic temperatures vary between those exhibited by the component polymers. Vigorous annealings failed to phase separate the components. The melting behavior of the annealed polymer sample suggests the crystalline components of the two polymers are cocrystallized in this unique compatible sy

ISSN:0032-3888    

DOI:10.1002/pen.760270611

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY