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Showing papers in "Polymer in 1969"


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: The laser-Raman spectrum of poly(methyl methacrylate) complete with depolarization data is reported in this article, and a spectrum of powdered poly(ethyl methacric acid) is also given for reference purposes.

234 citations



Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, the morphological changes which occur when partially crystalline poly(ethylene terephthalate) is annealed were aetected and followed quantitatively using differential scanning calorimetry.

111 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the gelation technique has been applied to the following monomers to determine the nature of the termination reactions in the free-radical polymerizations at 25°C: methyl, ethyl and n -butyl methacrylates; methyl and ethyl acrylsates; acrylonitrile and methacellitrile; vinyl acetate; the photo-initiating system used was manganese carbonyl + polyvinyl trichloracetate.

105 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the preparation and examination of a series of styrene-butadiene block copolymers cast from toluene solution was described, and regular structures were observed under the electron microscope and it appears that particular solvents may give rise to characteristic structures.

99 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, a new model to explain the twisting of ribbon-like crystals within spherulites is proposed, based on the inherent twisting perpendicular to the axis of a screw dislocation.

80 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, the anomalous characteristics of polyethylene oxide isotherms are partly attributable to the wide molecular weight distributions and low nucleation densities, and non-integral values of the Avrami exponent, n, are observed under conditions of high density of nuclei.

75 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, it is shown that fracture is preceded by the formation of crazes and that at a critical stage small voids form in the thickest part of the craze.

69 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the authors reviewed literature values for the heat of fusion of poly(ethylene terephthalate) and compared with values obtained using differential scanning calorimetry and from the melting point depression produced by dibutyl phthalate diluent.

67 citations


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, the Jacobson and Stockmayer equilibrium theory of macrocyclization was used to derive the dimensions of poly(dimethylsiloxane) chains with 40-80 chemical bonds in the bulk polymer at 110°C.

56 citations



Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the structure of β-keratin has been investigated using X-ray diffraction and infra-red data, and an alternative model with intra-sheet disorder was also considered.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the effects of molecular weight, catalyst residues, and nucleating agents on the rates of crystallization from the melt of polymers of poly(ethylene terephthalate) and related copolymers have been studied.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, the nature of primary radicals arising from the interaction of halides and organometallic derivatives has been investigated with the aid of tracer and gelation techniques, and the results for the ratio of combination to disproportionation in the termination reaction of methyl methacrylate polymerization are given for three temperatures.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, it was found that acrylamide which had been left standing in air for several weeks polymerized spontaneously in water at room temperature at a rapid speed of polymerization in spite of the absence of an initiator.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the authors have shown that the extent of rotation of the glycol fragment about the terephthalate framework in the PET crystal appears to be greater than in the above model.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, a sample of polymethylmethacrylate possessing lauryl-mercaptyl end groups has been fractionated by gel permeation chromatography, and measurements of the thermal degradation of the fractions have been performed by micro-pyrolysis-gas-liquid-chromatography.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: The thermal degradation at 180°C of polyvinyl chloride in two species of labelled toluene (C6H5CH2T and C6H514CH3) has been studied in this article.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the Jacobson and Stockmayer equilibrium theory of macrocyclization was used to calculate the concentrations of large ring molecules in commercial nylon 6, and the calculated concentrations of tetramer and pentamer were in accord with published experimental values.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, a method is described for preparing regular copolymers with repeat unit, where M is a vinyl or diene monomer, and R is the ligand of an aliphatic dihalide.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, a cloud point test was used to find θ solvents for random and block copolymers of styrene and methyl methacrylate, and various solvements were examined.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, 1,3-Dioxepan was polymerized under vacuum in methylene dichloride solution by anhydrous perchloric acid, resulting in a perfectly clean monomer-polymer equilibrium.

Journal ArticleDOI
A Lambert1
01 Jan 1969-Polymer
TL;DR: In this paper, a method to eliminate distortion due to finite injected weight by extrapolating data to zero injected weight has been developed for polystyrenes eluted by tetrahydrofuran.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, a triplet state mechanism for photoreduction of polyvinylbenzophenone (PVB) was shown to lead to cyclization when irradiated in dilute solutions and to crosslinking in concentrated solutions and solid films.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, solid phase polycondensation (ester interchange) reaction leading to the formation of polyethylene terephthalate has been studied and it is deduced that polymerization occurs only within a limited depth from the surface of each polymer particle.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: Lower critical solution temperatures (LCST) have been obtained for polyisobutylene and some thirty isomeric pentanes, hexanes, heptanes and octanes as discussed by the authors.


Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, an equation is given which relates the pressure p, density d and absolute temperature T of unassociated liquids, which can be used for polymeric liquids with c.s. units.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this article, the degree of polymerization determinations were made using light scattering, osmometry, gel permeation chromatography and viscosity techniques, and frequency distribution curves obtained.

Journal ArticleDOI
01 Jan 1969-Polymer
TL;DR: In this paper, an anionic polymerization procedure for preparing styrene and methyl methacrylate block copolymers is described, and the products are characterized by combustion analysis, osmometry, light scattering measurement, and gel permeation chromatography.