Showing papers in "Polymer in 1982"

TL;DR: In this article, a modification of permanganic etchant by incorporating orthophosphoric acid has been found which avoids formation of artefacts on polyethylene and other polyolefines allowing representative melt-crystallized morphologies to be studied with the electron microscope.

TL;DR: In this article, the tensile strength of poly(l-lactic) PLLA fibres with a high degree of molecular orientation and crystallinity were produced by hot drawing of the melt-spun and solution-sun fibres.

TL;DR: In this article, a theory is proposed to explain the transport behavior of organic penetrants in glassy polymers in terms of two basic parameters: the diffusivity of the penetrant, D, and the viscous flow rate of the glassy polymer, 1 η 0, which is considered to be diffusion of solvent down an activity gradient coupled with time-dependent mechanical deformation of the polymer glass in response to the swelling stress.

TL;DR: The diffusion of solutes in gels is comprehensively reviewed in this article, where precise definitions of the gel diffusion coefficient are presented and discussed, and the success of the theories in accounting for these results is examined.

TL;DR: In this paper, the morphology of epoxy resins modified with 5-15 parts by weight (pbw) of carboxyl (CTBN) and amine (ATBN) terminated butadiene acrylonitrile rubber have been characterized.

TL;DR: In this article, the crystallization, the morphology and the thermal behaviour of thin films of isotactic polypropylene (iPP) blended with elastomers such as random ethylene-propylene copolymers (EPM) with different ethylene content and polyisobutylene (PiB) were investigated by means of optical microscopy, differential scanning calorimetry and wide angle X-ray diffractometry.

TL;DR: In this article, the problem of the possible regimes of the qualitatively different behaviour of solutions of weakly charged polyelectrolytes in theta-and good solvents is considered.

TL;DR: A Tektronix-31 programmable calculator interfaced to a Perkin Elmer differential scanning calorimeter, model 2, substantially improves the accuracy of measuring the time-dependent development of the degree of crystallinity (× 10) and hence improves the quality of the rate data as mentioned in this paper.

TL;DR: In this paper, the structure-property relationship of a series of segmented polyurethanes was investigated segment was 4,4′-diphenylmethane diisocyanate (MDI) extended with 1,4-butanediol, and the soft segment was 2000 mw poly (tetramethylene oxide) ether.

TL;DR: In this article, a branched poly(3-hydroxybenzoate) was obtained by condensation of 3-(trimethylsiloxy) benzoyl chloride and 3,5-(bistrimethylsiloxide) benzoylel chloride.

TL;DR: In this paper, the structure of the hard segments in MDI/diol/PTMA polyurethanes was studied using X-ray diffraction and conformational analysis.

TL;DR: In this paper, the vibrational spectra of poly(ethylene terephthalate) in the crystalline and amorphous states and in solution were measured and the conformational forms of various conformational form were defined.

TL;DR: In this paper, a double helical model with long sequences of the same helical sense for phase I, but with less long range order and frequent reversals of helical senses for phase II has been interpreted in terms of a double-helical model.

TL;DR: In this article, the heat capacities of wood cellulose, other natural celluloses having various crystallinities and of lignin were given for temperatures ranging from 330K to 450K using differential scanning calorimetry.

TL;DR: In this article, composites of low density polyethylene, LDPE, and polyacetylene, (CH)x, were prepared by polymerization of acetylene in LDPe films impregnated with a Ti(OBu) 4 Et 3 Al Ziegler-Natta catalyst.

TL;DR: In this paper, the effect of thermal pre-treatments on yield stress and enthalpy change of polycarbonate was investigated. But the authors focused on the effects of pre-treatment on yield and densification.

TL;DR: In this paper, a determination of the nature of the interaction between the amine groups and the residual silanol groups in partially cured solids was made and compared with γ-aminopropylmethyldiethoxysilane and its analogues.

TL;DR: In this paper, the melting temperature of the principal crystalline lamellar phase (phase I) of PEO-Nal and PEO NaSCN-PEO-NaSCN complexes is independent of the nature of the anion.

TL;DR: In this article, a linear regression analysis was applied to the following relations: Fmax vs. (E′, tan δ; impact strength), F2max vs (tan δ, impact strength).

TL;DR: Chlorinated polyvinyl chloride (CPVC) was solution blended with poly(caprolactone) (PCL), poly(hexamethylene sebacate), PHMS, poly(α-methyl-α-n-propyl-β-propiolactone), PMPPL and PVL.

TL;DR: In this paper, a case was made for dual mode sorption kinetics with 40% of the water accommodated in microvoids and the remainder taken up by swelling, which appeared to be mutually inconsistent.

TL;DR: In this paper, the high-resolution 13 C n.m.r. spectra of three samples of solid isotactic polypropylene are reported under conditions of proton dipolar-decoupling and fast magic-angle rotation and using cross-polarization.

TL;DR: In this article, a large number of crosslinked polymer gels containing over 90% poly(ethylene oxide) have been made and their swelling has been studied and their interaction with water is quite different from the interaction with most other solvents.

TL;DR: In this article, a differential scanning calorimetry (d.s.c) approach was used to assess the morphology of polypropylene (PP) and thermoplastic rubber (TR) blends, such as the type of the dispersion (phase continuity) and the degree of the particle size.

TL;DR: In this paper, the authors measured the extension ratio λ max within crazes in nine blends of high molecular weight polystyrene (PS) and four blends of low molecular weight PS (whose molecular weight lies below its entanglement molecular weight M e ) with the same PPO.

TL;DR: In addition to chemical processes such as the hydrolysis of ester groups, there are physical processes contributing to the hygrothermal degradation of crosslinked polyester resins as mentioned in this paper.

TL;DR: In this paper, a comparison of the lamellar structure of copolymers polystyrene-poly(γ-benzyl- l -glutamate) (SG), polybutadiene-poly (γ-belzyl)- l-glutamide) (BG), and poly styrene poly(e-carbobenzoxy-l -lysine) (SCK) was made.

TL;DR: In this article, two rigid chain thermotropic liquid crystal polyesters have been examined by X-ray diffraction and thermal analysis in order to explore the nature of the crystallites in the solid state.

TL;DR: The semi-crystalline state of PET and its relation to the melting behavior of the polymer have been thoroughly investigated as a function of the thermal history by wide-angle X-ray diffraction.