Thin longitudinal sections (100 μm thick) were reacted with butyl isocyanate and octadecyl isocyanate under dry conditions. Weight gain and nitrogen analysis demonstrated reaction to degree of substitution about 0.9 (based on published wood cell wall analytical data). Infrared spectra data gave good evidence for the formation of carbamate ester (urethane bonds). Up to weight gain of about 30% no practically significant loss of tensile strength or toughness was observed. Above this level, strength and toughness was observed to fall as a function of weight increase, similarly with both reagents. Over the range examined the precise degree of substitution (loss of hydroxyl functionality) appeared to have no direct effect on mechanical properties. The strength losses seem to be related to cell wall rupture resulting from excessive swelling occurring at the higher levels of reaction.
{"title":"Mechanical Properties of Alkyl Isocyanate Modified Scots Pine Wood Surfaces","authors":"W. Banks, G. Jones","doi":"10.1002/PI.4980180412","DOIUrl":"https://doi.org/10.1002/PI.4980180412","url":null,"abstract":"Thin longitudinal sections (100 μm thick) were reacted with butyl isocyanate and octadecyl isocyanate under dry conditions. Weight gain and nitrogen analysis demonstrated reaction to degree of substitution about 0.9 (based on published wood cell wall analytical data). Infrared spectra data gave good evidence for the formation of carbamate ester (urethane bonds). Up to weight gain of about 30% no practically significant loss of tensile strength or toughness was observed. Above this level, strength and toughness was observed to fall as a function of weight increase, similarly with both reagents. Over the range examined the precise degree of substitution (loss of hydroxyl functionality) appeared to have no direct effect on mechanical properties. The strength losses seem to be related to cell wall rupture resulting from excessive swelling occurring at the higher levels of reaction.","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80979558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"VII Convegno Italiano di Scienza e Tecnologia delle Macromolecole","authors":"Francesco Ciardelli","doi":"10.1002/PI.4980180402","DOIUrl":"https://doi.org/10.1002/PI.4980180402","url":null,"abstract":"","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81500039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polymeric stabilization of colloidal dispersions. By D. H. Napper, Academic Press, London, 1984. pp. xviii + 428, price £39.50, $65.00. ISBN 0‐12‐513980‐2","authors":"A. S. Dunn","doi":"10.1002/PI.4980180420","DOIUrl":"https://doi.org/10.1002/PI.4980180420","url":null,"abstract":"","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75676779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polymers for fibres and elastomers. Edited by J. C. Arthur Jr, ACS Symposium Series No. 260, American Chemical Society, Washington D.C., 1984. pp. x + 433, price &69.95 (USA & Canada), $83.95 (rest of world). ISBN 0-8412-0859-X","authors":"S. Dawber","doi":"10.1002/PI.4980180423","DOIUrl":"https://doi.org/10.1002/PI.4980180423","url":null,"abstract":"","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73162229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Styrene was grafted from polyisoprene forming poly(isoprene-g-styrene) graft polymers. N,N,N',N'-Tetramethylene diamine and s-butyllithium were used to create active centres on the polyisoprene backbone in cyclohexane under anionic living polymerisation conditions. The stereoregularity of polyisoprene is shown to influence the grafting efficiency. Addition of small amounts of tetrahydrofuran increased grafting efficiency and decreased polydispersity of the graft polymers obtained. Polystyrene branches are shown to be syndiotactic rich.
{"title":"Anionic Graft Polymerisation of Styrene from Polyisoprene. Dependence of Grafting Efficiency on Polyisoprene Structure","authors":"M. Al-jarrah, J. K. Al-Kafaji, R. Apikian","doi":"10.1002/PI.4980180411","DOIUrl":"https://doi.org/10.1002/PI.4980180411","url":null,"abstract":"Styrene was grafted from polyisoprene forming poly(isoprene-g-styrene) graft polymers. N,N,N',N'-Tetramethylene diamine and s-butyllithium were used to create active centres on the polyisoprene backbone in cyclohexane under anionic living polymerisation conditions. The stereoregularity of polyisoprene is shown to influence the grafting efficiency. Addition of small amounts of tetrahydrofuran increased grafting efficiency and decreased polydispersity of the graft polymers obtained. Polystyrene branches are shown to be syndiotactic rich.","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79412032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The thermal degradation of polystyrene in the absence of oxygen is examined, at temperatures above or below 300°C. The decrease in degree of polymerisation occurring either with negligible volatilisation at lower temperatures, or with evolution of low molecular weight products at higher temperatures, is simulated by Monte-Carlo procedures. The results suggest that below 300°C, scission of the polymer chains is random, and involves also a minor fraction of some abnormal, as yet unidentified, structures. Above 300°C, an extensive intermolecular transfer process seems to be the main cause of the decrease in degree of polymerisation, whereas an overall depolymerisation of 100 structural units at each chain scission is the source of volatilisation.
{"title":"Thermal Degradation of Polystyrene","authors":"M. Guaita","doi":"10.1002/PI.4980180405","DOIUrl":"https://doi.org/10.1002/PI.4980180405","url":null,"abstract":"The thermal degradation of polystyrene in the absence of oxygen is examined, at temperatures above or below 300°C. The decrease in degree of polymerisation occurring either with negligible volatilisation at lower temperatures, or with evolution of low molecular weight products at higher temperatures, is simulated by Monte-Carlo procedures. The results suggest that below 300°C, scission of the polymer chains is random, and involves also a minor fraction of some abnormal, as yet unidentified, structures. Above 300°C, an extensive intermolecular transfer process seems to be the main cause of the decrease in degree of polymerisation, whereas an overall depolymerisation of 100 structural units at each chain scission is the source of volatilisation.","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80753975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aqueous solutions of polyallylamine hydrochloride were examined by small angle x-ray scattering. When the polymer concentration of coexisting simple salt was low, a single, broad peak was observed. The peak was interpreted as indicating the presence of an ordered arrangement of macroions in the solutions. The intermacroion spacing was calculated by the Bragg equation and found to be much smaller than the average intermacroion spacing calculable from the polymer concentration, suggesting that there exist ordered regions and at the same time disordered regions in the solutions. The Bragg spacing decreased with increasing polymer concentration and increased with increasing salt concentration. Mixing of two samples of different molecular weights gave a new scattering peak in between the original peaks of the mother samples, which supports the intermolecular nature of the ordering. The peak height was lowered with increasing temperature. The scattering peak was found to stay unaffected for 21 days.
{"title":"Ordered structure of polyallylamine hydrochloride in dilute solutions as studied by small angle X-ray scattering","authors":"Y. Yoshikawa, H. Matsuoka, N. Ise","doi":"10.1002/PI.4980180408","DOIUrl":"https://doi.org/10.1002/PI.4980180408","url":null,"abstract":"Aqueous solutions of polyallylamine hydrochloride were examined by small angle x-ray scattering. When the polymer concentration of coexisting simple salt was low, a single, broad peak was observed. The peak was interpreted as indicating the presence of an ordered arrangement of macroions in the solutions. The intermacroion spacing was calculated by the Bragg equation and found to be much smaller than the average intermacroion spacing calculable from the polymer concentration, suggesting that there exist ordered regions and at the same time disordered regions in the solutions. The Bragg spacing decreased with increasing polymer concentration and increased with increasing salt concentration. Mixing of two samples of different molecular weights gave a new scattering peak in between the original peaks of the mother samples, which supports the intermolecular nature of the ordering. The peak height was lowered with increasing temperature. The scattering peak was found to stay unaffected for 21 days.","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84200049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tribologie der Polymere. H. Uetz and J . Wiedemeyer, Hanser, Munich and Vienna, 1984. pp. x+378, price DM198.00. ISBN 3‐446‐14050‐6","authors":"W. Wake","doi":"10.1002/PI.4980180320","DOIUrl":"https://doi.org/10.1002/PI.4980180320","url":null,"abstract":"","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74629070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The stress-strain properties of three different rubbers have been measured using two different techniques, in order to evaluate the relative internal energy contribution to the total stress fe/f and the corresponding value of Me/M over a range of strain and temperatures. Two different experimental techniques have been designed; one is to allow measurement in simple extension of the length of a rubber sample in relation to the temperature at constant force, and the other is to measure the variation of torsional couple M in a cylinder of rubber (subjected to combined torsion about the axis and extension in the axial direction) with temperature. The thermoelastic results obtained for natural rubber and butyl rubber do not contain any surprising features, and are found to be in good agreement with other reported experimental results for these rubbers. Values of fe/f and Me/M obtained for cis-trans polybutadiene rubber show different trends between the two techniques.
{"title":"An Experimental Study of the Thermodynamics of Rubber in Extension and Torsion","authors":"M. Mohsin, J. P. Berry, L. Treloar","doi":"10.1002/PI.4980180302","DOIUrl":"https://doi.org/10.1002/PI.4980180302","url":null,"abstract":"The stress-strain properties of three different rubbers have been measured using two different techniques, in order to evaluate the relative internal energy contribution to the total stress fe/f and the corresponding value of Me/M over a range of strain and temperatures. Two different experimental techniques have been designed; one is to allow measurement in simple extension of the length of a rubber sample in relation to the temperature at constant force, and the other is to measure the variation of torsional couple M in a cylinder of rubber (subjected to combined torsion about the axis and extension in the axial direction) with temperature. The thermoelastic results obtained for natural rubber and butyl rubber do not contain any surprising features, and are found to be in good agreement with other reported experimental results for these rubbers. Values of fe/f and Me/M obtained for cis-trans polybutadiene rubber show different trends between the two techniques.","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85205086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Synthetic polymer membranes ‐ a structural perspective, 2nd edition. By Robert E. Kesting, John Wiley & Sons, Chichester & New York, 1985. pp xii+348, price i55.75. ISBN 0‐471‐80717‐6","authors":"C. Finch","doi":"10.1002/PI.4980180318","DOIUrl":"https://doi.org/10.1002/PI.4980180318","url":null,"abstract":"","PeriodicalId":9298,"journal":{"name":"British Polymer Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1986-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82174780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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