The polymerisation of methylmethacrylate initiated by alkali alkoxides is greatly promoted in the presence of macrocyclic compounds, cryptands and crown ethers. The solubility in toluene and the reactivity of alkoxides is enhanced by these complexing agents. Polymerisations have been carried out in a non-polar solvent in the homogeneous phase.
{"title":"Homogeneous polymerisation of methylmethacrylate initiated by alkali metal salts of methanol and t-butyl alcohol in the presence of cryptands and macrocyclic crown ether compounds","authors":"M. Viguier, A. Collet, F. Schué, B. Mula","doi":"10.1002/PI.4980180306","DOIUrl":"https://doi.org/10.1002/PI.4980180306","url":null,"abstract":"The polymerisation of methylmethacrylate initiated by alkali alkoxides is greatly promoted in the presence of macrocyclic compounds, cryptands and crown ethers. The solubility in toluene and the reactivity of alkoxides is enhanced by these complexing agents. Polymerisations have been carried out in a non-polar solvent in the homogeneous phase.","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":"87133573","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}
Continuation of work on the curing characteristics of an epoxy resin which is widely used as a composite matrix is reported. Results are given of study of the cure of the resin with dicyandiamide as hardener and diuron as accelerator, using differential scanning calorimetry to monitor the cure. The effect of diuron on the cure of the resin with an aromatic amine curing agent is also described. Distinctive effects of composition are found and values of the apparent activation energy of the curing reaction are derived.
{"title":"Differential Scanning Calorimetry Cure Studies of Tetra‐N‐glycidyldiaminodiphenylmethane Epoxy Resins 3 ‐ Reaction with Dicyandiamide","authors":"J. M. Barton, D. Greenfield","doi":"10.1002/PI.4980180311","DOIUrl":"https://doi.org/10.1002/PI.4980180311","url":null,"abstract":"Continuation of work on the curing characteristics of an epoxy resin which is widely used as a composite matrix is reported. Results are given of study of the cure of the resin with dicyandiamide as hardener and diuron as accelerator, using differential scanning calorimetry to monitor the cure. The effect of diuron on the cure of the resin with an aromatic amine curing agent is also described. Distinctive effects of composition are found and values of the apparent activation energy of the curing reaction are derived.","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":"81409917","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}
High resolution 13C n.m.r. data are presented for a series of model compounds generated by the acid catalysed reaction of either phenol or cresol with formalin. The pure compounds prepared for this study allow unambiguous identification of features associated with ortho-ortho, ortho-para and para-para linked moieties, and hence allow analysis of the sequence structure in the typical resin. To aid assignment of the spectra a comparison is made between the predictions of the spectra using simple additivity relationships and the experimentally observed shifts. It is found that the differences between theory and experiment vary systematically with structure, and averaged correction factors are presented for various characteristic structures.
{"title":"13C Nuclear Magnetic Resonance Studies of Phenol‐Formaldehyde Resins 1 ‐ Model Compounds","authors":"R. Pethrick, B. Thomson","doi":"10.1002/PI.4980180307","DOIUrl":"https://doi.org/10.1002/PI.4980180307","url":null,"abstract":"High resolution 13C n.m.r. data are presented for a series of model compounds generated by the acid catalysed reaction of either phenol or cresol with formalin. The pure compounds prepared for this study allow unambiguous identification of features associated with ortho-ortho, ortho-para and para-para linked moieties, and hence allow analysis of the sequence structure in the typical resin. To aid assignment of the spectra a comparison is made between the predictions of the spectra using simple additivity relationships and the experimentally observed shifts. It is found that the differences between theory and experiment vary systematically with structure, and averaged correction factors are presented for various characteristic structures.","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":"76624601","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}
Hydrolysis of poly(6,8-(1,5-dichloro-2,4-dioxa-3-keto)bicyclo[3.3.0]octylene vinylene) results in the formation of poly(4,5-bis-hydroxy-1,3-cyclopentadienylene vinylene), a new conjugated polymer. This new system can be generated as a surface layer on its precursor polymer. The conversion process has been studied with the aid of infrared and optical spectroscopy, elemental analysis, microscopy and conductivity measurements.
{"title":"Synthesis of poly(4,5-bis-hydroxy-1,3-cyclopentadienylene vinylene) from poly(6,8-(1,5-dichloro-2,4-dioxa-3-keto)-bicyclo [3.3.0] octylene vinylene). Generation of a conjugated polymer by hydrolysis of a precursor polymer","authors":"W. Feast, Kevin Harper","doi":"10.1002/PI.4980180305","DOIUrl":"https://doi.org/10.1002/PI.4980180305","url":null,"abstract":"Hydrolysis of poly(6,8-(1,5-dichloro-2,4-dioxa-3-keto)bicyclo[3.3.0]octylene vinylene) results in the formation of poly(4,5-bis-hydroxy-1,3-cyclopentadienylene vinylene), a new conjugated polymer. This new system can be generated as a surface layer on its precursor polymer. The conversion process has been studied with the aid of infrared and optical spectroscopy, elemental analysis, microscopy and conductivity measurements.","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":"75940812","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 flow characteristics of styrene-butadiene-styrene thermoplastic rubbers have been studied and the results compared with earlier static measurements. Computer best-fitting shift factors and inverse Melt Flow Index were plotted according to two mathematical models, Arrhenius and Vogel. Fulcher, Tamman and Hesse (VFTH). One transition was observed in both models, with appreciable reduction in the apparent activation energy of flow above this transition. This melt transition was associated with the temperature above which the PS chains can be removed from the PS rich phase by the rubbery chains. This allows rearrangement of the domain structure in a static condition or facilitates flow. Birefringence measurements support the model proposed.
{"title":"Molten State Transition in Thermoplastic Rubber","authors":"S. Canevarolo, A. Birley, D. Hemsley","doi":"10.1002/PI.4980180310","DOIUrl":"https://doi.org/10.1002/PI.4980180310","url":null,"abstract":"The flow characteristics of styrene-butadiene-styrene thermoplastic rubbers have been studied and the results compared with earlier static measurements. Computer best-fitting shift factors and inverse Melt Flow Index were plotted according to two mathematical models, Arrhenius and Vogel. Fulcher, Tamman and Hesse (VFTH). One transition was observed in both models, with appreciable reduction in the apparent activation energy of flow above this transition. This melt transition was associated with the temperature above which the PS chains can be removed from the PS rich phase by the rubbery chains. This allows rearrangement of the domain structure in a static condition or facilitates flow. Birefringence measurements support the model proposed.","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":"74825032","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 reactions of mono- and difunctional tertiary amine ended polybutadienes with mono- and difunctional living cationic poly THF have been studied. It is shown that the reaction to form quaternary ammonium linking groups takes place rapidly in all cases, and AB. ABA, BAB and (AB) block copolymers have been prepared. The efficiency of the process is extremely high and the degree of conversion is essentially controlled by the efficiency with which the terminal tertiary amine groups can be introduced on to the polybutadiene. The block copolymers show anomalous behaviour on gel permeation chromatography columns and this has been related to a specific interaction of the created ionic groups with polar species on the column packing. This effect is greatest with (AB) block copolymers where substantial proportions are retained indefinitely on the columns.
{"title":"Reactions of Living Polytetrahydrofuran with Amines V ‐ Tertiary Amine Terminated Polybutadienes; The Synthesis of Novel Ionically Linked Block Copolymers","authors":"J. Hurley, D. H. Richards, M. J. Stewart","doi":"10.1002/PI.4980180308","DOIUrl":"https://doi.org/10.1002/PI.4980180308","url":null,"abstract":"The reactions of mono- and difunctional tertiary amine ended polybutadienes with mono- and difunctional living cationic poly THF have been studied. It is shown that the reaction to form quaternary ammonium linking groups takes place rapidly in all cases, and AB. ABA, BAB and (AB) block copolymers have been prepared. The efficiency of the process is extremely high and the degree of conversion is essentially controlled by the efficiency with which the terminal tertiary amine groups can be introduced on to the polybutadiene. The block copolymers show anomalous behaviour on gel permeation chromatography columns and this has been related to a specific interaction of the created ionic groups with polar species on the column packing. This effect is greatest with (AB) block copolymers where substantial proportions are retained indefinitely on the columns.","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":"90274637","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":"Polyacetylene: Chemistry, physics, and material science. James C. W. Chien, Academic Press, Orlando, Florida, 1984. pp. xiv+634, price $89.00. ISBN 0-1 2- 172460-3","authors":"W. Feast","doi":"10.1002/PI.4980180314","DOIUrl":"https://doi.org/10.1002/PI.4980180314","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":"85118945","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}
This research programme has been concerned with the technology of phenol-formaldehyde resins and of moulding powders based on them. This paper reports the characterisation of the prepolymer (Novolak) and concentrates on the results obtained by gel permeation chromatography with an infrared detector. A variety of frequencies have been employed, corresponding to different components in the resin, and the best separation was obtained by monitoring the phenolic hydroxyl at 3400 cm−1. It has been concluded that both commercial Novolak and prepolymer extracted from moulding powder contain a substantial fraction of high molecular weight material.
{"title":"The Technology of Phenol‐Formaldehyde Moulding Powders 1 ‐ Characterisation of Novolak Resins and Derived Moulding Powders","authors":"A. Birley, Arthur Blinkhorn","doi":"10.1002/PI.4980180303","DOIUrl":"https://doi.org/10.1002/PI.4980180303","url":null,"abstract":"This research programme has been concerned with the technology of phenol-formaldehyde resins and of moulding powders based on them. This paper reports the characterisation of the prepolymer (Novolak) and concentrates on the results obtained by gel permeation chromatography with an infrared detector. A variety of frequencies have been employed, corresponding to different components in the resin, and the best separation was obtained by monitoring the phenolic hydroxyl at 3400 cm−1. It has been concluded that both commercial Novolak and prepolymer extracted from moulding powder contain a substantial fraction of high molecular weight material.","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":"86441629","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":"Adhesives in engineering design. By W. A. Lees, The Design Council, London, 1984. pp. 152, price £16.95. ISBN 0-85072-150-4","authors":"V. Vohralík","doi":"10.1002/PI.4980180322","DOIUrl":"https://doi.org/10.1002/PI.4980180322","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":"73430420","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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