Chlorine-containing Polymers Research Articles

Re‐use of chlorine‐containing polymers

AbstractPoly(vinyl chloride) (PVC) and some other chlorine‐containing polymers belong to one of the most widely applied groups of thermoplastics. Their main disadvantage is the rather limited thermal stability, which requires the addition of heat stabilizers to prevent dehydrochlorination and discolouration. Hydrogen chloride is also the main volatile decomposition product during combustion of PVC; therefore, PVC‐waste is less suited for the so‐called thermal recycling. For the re‐use of PVC and similar polymers it is necessary to characterize these products by molecular weight (or at least viscometry), internal double bonds and other defect structures, stability against the influence of heat (and in some cases of light) and a few other properties. The application of these methods for deciding about the re‐usability of PVC roofing sheets and for the injection moulding of PVC scrap is demonstrated.

A Study of the Interaction of Phthalate Esters with Chlorine-Containing Polymers

The infrared spectra of blends of various ortho-phthalate esters with polyvinyl chloride) and vinylidene chloride/(20%)acrylonitrile copolymer were recorded. The data indicate that the lowering of the ester carbonyl absorption frequency is due to a dipole-dipole/complex type interaction between the carbonyl of the ester and the chlorine of the polymer in addition to hydrogen bonding with acidic hydrogens. The lowering of the absorption frequence increases with an increase in the amount of chlorine in the polymer chain.

Miscibility of poly(tetrahydrofurfuryl methacrylate) and poly(tetrahydropyranyl‐2‐methacrylate) with some chlorine‐containing polymers

Journal of Applied Polymer ScienceVolume 43, Issue 9 p. 1775-1775 ErratumFree Access Miscibility of poly(tetrahydrofurfuryl methacrylate) and poly(tetrahydropyranyl-2-methacrylate) with some chlorine-containing polymers Y. F. Chong, Y. F. Chong Department of Chemistry, National University of Singapore, Singapore 0511Search for more papers by this authorS. H. Goh, S. H. Goh Department of Chemistry, National University of Singapore, Singapore 0511Search for more papers by this author Y. F. Chong, Y. F. Chong Department of Chemistry, National University of Singapore, Singapore 0511Search for more papers by this authorS. H. Goh, S. H. Goh Department of Chemistry, National University of Singapore, Singapore 0511Search for more papers by this author First published: 5 November 1991 https://doi.org/10.1002/app.1991.070430921Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume43, Issue95 November 1991Pages 1775-1775 RelatedInformation

Differential Thermal Analysis of Polyacrylonitrile in the Presence of Chlorine-Containing Polymers

Abstract A differential thermal analysis (DTA) of polymer blends of polyacrylonitrile (PAN) with poly (α-chloroacrylonitrile) (PCAN) and poly (vinyl chloride) (PVC), prepared by coprecipitation from a solution containing both polymers, was carried out under nitrogen. Even if a small amount of PCAN or PVC was added to PAN, the exotherm peak position due to violent polymerization of the cyano groups, which appears at ca. 260°C in pure PAN, shifts to the higher-temperature side by ca. 40°C and its intensity becomes lower. Moreover, a new generation of heat is observed above ca. 220°C and ca. 260°C in the case of PAN–PCAN and PAN–PVC, respectively. These results were associated with the HCl generated during the heating process, since the chlorine atom formed by the reaction of a thermally degraded PAN polymer radical with HCl can both initiate polymerization of the cyano groups in PAN and terminate progress in polymerization by combination. Namely, DTA behavior could be explained by the effect of initiation (in the case of PAN–PCAN) and termination (in the case of PAN–PVC) upon the polymerization of cyano groups both below and above the temperature, respectively, at which PAN begins to be subjected to a sharp transition.

Thermal degradation of epoxidized soybean oil in the presence of chlorine-containing polymers

The thermal degradation of epoxidized soybean oil has been examined using thermal and spectroscopic methods. In both the presence and absence of chlorine-containing polymers, epoxidized soybean oil undergoes thermal degradation to form ring-opened products. In the absence of other reactants, the primary degradation reaction is apparently intermolecular ether formation. The degradation in a highly-chlorinated polymer matrix appears to be facilitated by reaction with hydrogen chloride generated by polymer degradation. Fully epoxidized soybean oil (7.0 wt.% oxirane oxygen) appears to contain two types of oxirane groups: type I which begins to undergo thermal ring-opening at about 175 °C and type II which opens at ⪢ 325 °C. Both ring openings are exothermic and irreversible. Type I oxirane groups account for approximately one-third of the total oxirane content of fully epoxidized soybean oil. Partially epoxidized soybean oil (3.28 wt.% oxirane oxygen) contains only type II oxirane functionality.

Sulfonation of chlorine-containing polymers: Sulfonation of various model tert-alkyl chlorides

tert-Alkyl chlorides of the structure R-C(CH3)2Cl, where R-methyl, ethyl, tert-butyl, and neo-pentyl, were reacted with a stoichiometric quantity of acetyl sulfate at room temperature in methylene chloride diluent. Reaction conversion was monitored as a function of time using 1H NMR; structure of the sulfonated products was characterized using 1H and 13C NMR. Reactivity toward sulfonation increased with increasing size of the R group. In all cases the structure of the products was the same as would be expected from sulfonation of the olefin which results from dehydrochlorination of the tert-chloride. The observed behavior was consistent with a mechanism involving dehydrochlorination followed by addition of SO3 to yield a zwitterionic intermediate. Depending upon structure, the zwitterion may either eliminate a proton to form one or more isomeric β,γ-unsaturated sulfonic acids, or it may rearrange to form a five-membered γ-sultone. This chemistry, which is particularly useful in the synthesis of ionomers, represents a direct route to alkyl sulfonic acids when the alkyl halide is the natural starting point in the synthesis.

Miscibility of poly(acetonyl methacrylate) with some chlorine-containing polymers

The miscibility of poly(acetonyl methacrylate) (PACMA) with some chlorine-containing polymers was studied by differential scanning calorimetry. PACMA is miscible with poly(vinyl chloride) and poly(chloromethyl methacrylate) and partially miscible with a vinylidene chloride/vinyl chloride copolymer, polyepichlorohydrin and an epichlorohydrin/ethylene oxide copolymer. The miscibility behaviour of PACMA is compared to those of poly(n-propyl methacrylate) and poly(isopropyl methacrylate).

US 4,849,466 stabilized chlorine-containing polymers

US 4,849,466 stabilized chlorine-containing polymers

Reaction of chlorine-containing polymers with polyethyleneimine

Specific features of the reaction between polyethyleneimine and polymers with reactive, allyl-type chlorine atoms — poly(1,1-dichlorobutadiene) and poly(1,1,2-trichlorobutadiene) — were studied. The reaction between the reactive groups on these polymers proceeds via an equilibrium charge-transfer complex, which is subsequently rearranged to a stable compound (paired polymer) with covalent C-N bonds.

Direct pyrolysis mass spectrometry of chlorine‐containing polymers using capillary GC/MS

AbstractA direct pyrolysis mass spectrometric technique has been developed and applied to several chlorine‐containing polymers. The capillary column in the gas chromatograph has been replaced by uncoated fused silica tubing to avoid the problem of column degradation induced by the polymer pyrolyzates. Under appropriate conditions, the pyrolysis mass spectra were found to be highly reproducible and to serve as “fingerprints.” The technique can be readily applied to carbon‐black‐filled, crosslinked elastomers, as well as polyblends and composites. The quantitative aspects of the technique have also been addressed.

Investigation of the influence of metal oxides on the thermal degradation of chlorine-containing polymers by thermogravimetry

The influence of oxides of zinc, magnesium, antimony and aluminium on the thermal degradations of polychloroprene, chlorinated polyethylene and epichlorhydrin homopolymer has been investigated. The investigations showed that these metal oxides can change the thermal stabilities and degradation processes of chlorine-containing polymers. A considerable acceleration of the dehydrochlorination of these polymers was found in the presence of zinc oxide.

Automatic equipment for studying the processes of low-temperature dehydrochlorination of chlorine-containing polymers

A multichannel, highly sensitive installation for the study of the kinetics of decomposition of halogen-containing polymers under automatic conditions has been described. Hydrogen halide produced by polymer decomposition is recorded using mercury-halide ion-selective electrodes, the results being processed by computer. Low-temperature (313–403 K) degradation of poly(vinyl chloride) has been studied. At the glass transition temperature (358 K) the Arrhenius parameters for the degradation of PVC change. A dependence between the segmental mobility of PVC macromolecules and the rate of polymer dehydrochlorination is demonstrated.

Methods of investigation Automatic equipment for measuring the low-temperature dehydrochlorination of chlorine-containing polymers

A high sensitivity automatic apparatus for measuring the rate of dehydrochlorination of chlorine-containing polymers is described.

Thermal stability of chlorine-containing polymers and its influence on their compatibility with polymethyl methacrylate

Phase diagrams have been constructed for the system PVC-PMMA and for the chlorinated PE-PMMA system, using a method of electron-probe microanalysis. A kinetic study has been made of the dehydrochlorination of chlorinated samples during the isobaric-isothermal annealing processes. It was found that solubility of the polymers is a function of the degree of dehydrochlorination. A study was made of the extent to which conditions of preparation of polyblends affects compatibility of the components and influences changes in compatibility observed in the course of annealing. Thermally induced phase separation in the polyblends occurs as a result of the above mentioned kinetic processes.

Investigation of thermal degradation of polymers containing chlorine by thermogravimetry

The thermal degradation of chlorine-containing polymers used in a rubber technology has been investigated in a nitrogen atmosphere. The characteristics of degradation have been compared on the basis of thermogravimetry, carbon residues and chlorine elimination. The observed structure-dependent differences in degradation of the investigated polymers are discussed.

Electrostatic property of ACS blendmer and chlorine-containing polymer

The ACS blendmer composed of chlorinated poly(ethylene) (CPE) and acrylonitrilestyrene copolymer is known to show an anti-electrification property. The electrostatic property of ACS blendmer and chlorine-containing polymers is studied, attention being given to their chemical structure and molecular motion. In particular, the charge decay process in these polymers is studied. It is found that the anti-electrification property of ACS blendmer depends on the electric property of CPE, and the surface charges are considered to decay quickly through the CPE moiety. The large charge decay constant of CPE, which is in a rubbery state at room temperature, results from the large mobility of the ion accompanied by a vigorous molecular motion. In polymers having a rubbery state, the charges decay more quickly than in those having a glassy state. It is concluded that the electrostatic property of polymers is affected by the molecular motion of polymers as well as the chemical structure.

High-temperature resisting fibres from chlorine-containing polymers

In this communication the writers investigate the feasibility of increasing the heat resistance of fibre from the copolymer of vinyl chloride with acrylonitrile (VC/AN) with added p-structure polyamide (PA) as described by A. T. Serkov [5]. Solutions of mixtures of VC/AN and PA in various proportions were prepared in dimethylacetamide (DMAA), the fibres being produced by precipitation in aqueous liquors containing 40-45 wt. % DMAA. The fibres were washed in water and ethanol, dried to a constant weight, and heated in a compact package for 4 h at 140°C in vacuo. The chlorine content of the specimens was determined by microanalysis.

Antimony-Chlorine Synergistic Effects on the Oxygen Index of Chlorine-Containing Polymers

Antimony-Chlorine Synergistic Effects on the Oxygen Index of Chlorine-Containing Polymers

The mechanism of the reaction of polymers containing chlorine with polydienes in the presence of amines

Organic compounds containing chlorine are used extensively for vulcanization of rubbers. Amines accelerate this process and increase the degree of structure formation [2]. It has been suggested that the accelerating effect of amines in crosslinking by hexachloroethane is brought about through the formation of an intermediate complex. The existence of this complex has not however been confirmed experimentally. The reaction of polydienes with chlorine-containing polymers has not been studied, although such systems would be of interest for the production of compositions with new properties. Moreover such reactions occur in the formation of adhesive bonds between rubbers and various substrates by means of adhesive compositions based on chlorine-containing polymers, in the course of vulcanization.

Pyrolysis-Gas Chromatographic Determination of Chlorine in Chlorine-Containing Synthetic Polymers

Abstract A new, simple and rapid method for determining chlorine in chlorine-containing polymers was investigated by means of pyrolysis-gas chromatography. Hydrogen chloride evolved during the thermal degradation of the polymers was eliminated by a NaOH precut column, and only the organic compounds sensitive to flame ionization detector were separated to record the pyrograms. Chlorine content of the polymers was calculated from the relative yield of the degradation products using a theoretical equation deduced from the degradation mechanisms of the polymers. This unique method permits very rapid determination of chlorine with the use of about 0.1 mg of the sample without either the use of calibration curves or weighing of the samples.