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Aspects of the influence of the macrokinetics on the MM and MMD of a polymeric product formed in turbulent flow are examined. The specific phenomena of the influence of the amount of catalyst applied to the reaction zone and the number of reaction zones in conditions of adiabatic heating of the reaction mixture and different variants of heat removal on the MM and MMD of the polymer have been identified and quantitatively estimated. The conduct of fast polymerization processes calls for special methods of investigation and an individual approach to the implementation of the technological process: different grades (according to the MM and MMD) of the polymer may be obtained by changing the system of supply of catalyst and the means of heat removal. Some specific variants of the conduct of the process of oligo- and polymerization are considered. The non-traditional behaviour of rapid polymerization processes raises the problem of allocating them to a separate class of polymerization reactions.

The catalytic degradation of polyolefins in the presence of proton-donor complex compounds has been investigated. It is shown that the polyolefin structures (structure of the repeat-units, presence of double bonds and of branching stemming from the conditions of polymer preparation, molecular mass characteristics) influence features of processes of degradative changes occurring in polyolefins and affect selectivity in the formation of reaction products.

In the absence of an emulsifier the graft polymerization of methyl acrylate to water soluble polysaccharides obeys the main regularities of emulsion polymerization processes. The polymerization rate in the second stage of the process studied (up to a 40–50% degree of conversion) remains constant on account of the gel effect. The kinetic parameters of the reaction were found to be in keeping with the proposed kinetic scheme.

The main reasons for the formation of intermolecular associates of conjugated polymers have been considered. It was found that paramagnetic centres play a determining role in these processes. Their role amounts to the formation of weak chemical bonds. Possible mechanisms of formation of the paramagnetic centres were discussed. It is thought that a determining role is played by the formation of biradicals and by thermal occupation of low energy triplet levels. The local activation effect is thought to consist in the removal of the prohibition of singlet-triplet transitions in the course of the reaction.

The reaction of 1,4-bis-(phenylglyoxalyl)benzene with 3,3′,4,4′-tetramino diphenyloxide was used as an example to find the optimum conditions for the synthesis of polyphenylquinoxalines (PPQ) having a large mol.wt. Seven polymers were produced with ligand groups in the amine and ketone components; their thermal, chemical and mechanical properties have been studied.

Investigations of rubbers combined with oligoester acrylates (OEA) have shown the heterogeneous nature of these systems. The sizes of OEA inclusions in the rubber-oligomer mixtures were determined before and after vulcanization by optical microscopy methods. It was found that the morphology and mechanical properties of the vulcanizates depend, in the case of the studied oligomer, on its compatibility with the rubbers and on the conditions of prior treatment of the initial mixtures.

The influence of the nature and composition of reinforcing fibres and polymer binders (epoxide and phenolic resins) on the degradation and combustion of composite materials based on them has been studied.

The influence of thermophysical and thermochemical properties on flame propagation velocity has been investigated. It is shown that the polymer behaviour at oxygen concentrations exceeding 35% may be characterized by the heat of combustion and by the thermal conductivity coefficient. The correlation equation νp = (0·14 + 1·8 × 10−8 Q/ks) Y0(1·35+0·88×10−4Q) has been derived. Some cases have been examined in the light of this relationship to determine flame propagation velocities over polymer and composite surfaces.

A new approach to regulating polymer structure is suggested which is based on experimental results. It is a thermodynamic method of regulating macromolecular and molecular structures. The essence is a synthetic method under near-equilibrium monomer-polymer conditions. The polymerization of trioxane in various solvents is used as an example to show the suitability of such an approach. Trioxane copolymerization with dioxolane in methylene chloride or nitrobenzene is also examined.

The model that has been proposed for the heterogeneous polymerization of tetrafluoroethylene assumes that chain termination takes place through the recombination of radicals displaced solely on account of the addition of monomer in acts of chain propagation. Equations describing the kinetics of the process under post-polymerization conditions have been derived. It is shown that the process may be described using only one kinetic constant, i.e. the propagation rate constant. The proposed model has been verified by experiment.

Light is thrown on features of the anionic polymerization of phenylacetylene, the main one being the extinction of the process with unreacted monomer present in the system. This is considered from the point of view of intra- and intermolecular deactivation. The former is the result of exchange interaction of active centres with the π-electron system of the growing polyphenylacetylene chain, while the latter is due to the formation of complex associates of growing polyphenylacetylene chains.

Using a model system chain transfer to an oligomer unit was studied during polymerization of dimethacrylic esters of oligotetramethylene glycols. It was found that chain transfer has a very slight, negligible effect on the overall reaction system. The constant of the reaction of chain transfer to the elementary unit of oligotetramethylene oxide was evaluated.

Studies were made of kinetic features of radical polymerization of 1-vinyl-1,2,4-triazole and the molecular weight variation of poly-1-vinyl-1,2,4-triazole in water, in DMF and in DMAA. The rate of polymerization of the monomer in water and MW of the polymer obtained is higher than in other solvents. MW of poly-1-vinyl-1,2,4-triazole is proportional to the concentration of the monomer. It was shown that a typical feature of polymerization, which is general for all the solvents studied, is the existence of a reaction rate for the initiator with a reaction order higher than 0·5. The mechanism of monomolecular decay of macroradicals is discussed. The effective activation energy of polymerization was found.

The chemical reaction kinetics due to a lack of translational diffusion are examined in crosslinked polymers. Equations have been derived for a bimolecular reaction of the macromolecules in the network. Mathematical models of the process are given and the justification of modelling, as well as the calculation results are dealt with.

The thermal, thermohydrolytic and thermooxidative degradation of polynaphthoylene benzimidazoles (PNBI) differing in their chemical structures has been investigated in the temperature interval 250–600°. It is shown that at high temperatures PNBI specimens decompose by a radical mechanism, and that the radical degradation is due to random opening of covalent bonds of heterocyclic fragments. Comparable degrees of cyclization were observed for PNBIs prepared in polyphosphoric acid and by means of high-temperature catalytic polycyclocondensation in organic solvents.

The inflammability of polymers by electrically heated cylinders, simulating low-calorific sources, has been studied. It has been shown that for any polymer, there is a minimum temperature of the cylinder's surface, Ti, above which the polymer catches fire. It has been observed that Ti decreases as the air temperature and cylinder diameter increase. It is concluded that Ti characterizes the combustibility of the mixture consisting of the products of degradation and air and, together with the induction period for ignition, may be used as an assessment of the inflammability of polymers under the action of low-calorific sources.

Aromatic N,N′-bis-(acetylnitroso)diamines have been used to synthesize heat-resistant polymers—the polyazophenylenes (PAP) — having different ligand groups between the benzene rings, and their physico-chemical properties have been studied. Methylene-, ester-, sulphone- and sulphide-groups introduced as ligands do not alter the properties of the PAP from those of polymers with a system of conjugations. The presence of an aqueous phase in the polymerization system has been found to ensure an effective removal of the acetoxy radicals from the reaction zone; the resulting PAP had a larger molecular weight.

It was established that phenothiazine mixed with concentrated sulphuric acid inhibits polymerization of methyl acrylate as a consequence of the formation of phenothiazine cation radicals.

Low molecular weight products of the condensation of dianhydride of perylene tetracarboxylic acid (DAPTA) with tetra-aminodiphenyl ester (TADPE) and high molecular weight soluble polyaminoamido acids containing alternating naphthalene and perylene units, were obtained in an aprotonic solvent-inorganic salt system. The effect of various factors (LiCl concentration, concentrations of initial components, reaction temperature and dianhydride ratio) on the rate of polycondensation and the molecular weight of polyaminoamido acids was examined. Conditions of cyclization were determined for copolymers. Poly-(aroylene-bis-benzimidazoles) containing alternating perylene and naphthalene units were prepared by high temperature polycondensation in polyphosphoric acid.

The methods of reverse gas chromatography and successive integral sorption have been used to determine the free energies of mixing of cis -polyisoprene (SKI-3) and butadiene-nitrile copolymers (SKN-18 and SKN-26) with an α, ω-dimethacrylate (of triethyeneglycol): the values from these determinations agree satisfactorily. It has been shown that the system SKN-26-TGM-3 is compatible and thermodynamically stable over the entire range of compositionj and is characterized by negative values of ζ′ 23 . The compatibility of the components is impaired as the polarity of the rubber is decreased. SKI-3 rubber is practically incompatible with TGM-3.

An identification method for the prepolymer of polynaphthoylenebenzimidazole (PNBI) has been worked out on the basis of 13C—{1H} spectroscopy; a quantitative evaluation of the amino-amide and naphthoylenebenzimidazole fragment contents in the polymers has been carried out.

The effects of urea, temperature and reaction time on the proportions of the various fractions obtained in the polymerization of tetracyanobenzene at 300°C have been studied and the optimum conditions for the formation of polyphthalocyanines soluble in acetone and DMF have been derived. It has been shown that with prolonged heating the soluble polyphthalocyanines lose their solubility and become completely identical to the polymers synthesized in the presence of considerable (more than 50 mole %) quantities of urea.

The thermo-oxidative degradations (TOD) of polyaroylene-bis-benzimidazoles, synthesized from naphthalene-1,4,5,8- or perylene-3,4,9,10-tetracarboxylic acids and diaminobenzidine or tetraaminodiphenyl ether, of their copolymers, and of some low mol.wt. models, were studied. The TOD was found to be complicated and to be initiated by various reactive centres, thus creating differences in the actual reaction progress. Vacuum heat treatment at 300–400°C enhanced the resistance of the materials to TOD. Insertion of perylene blocks produced an extremal dependence of resistance to TOD on the ratio of perylene to napthalene chain units.

It was found that the stabilizing action of carboxylates of Cd and Pn influencing the thermal degradation of PVC is exhibited not only in HCl acceptance but also in inhibition of the reaction of polyene formation. This is due to replacement of Cl atoms in ∼ CO(CH = CH)nCHCl∼ groups by ester fragments of the stabilizer. A kinetic scheme of the reaction is discussed.

An analytical method has been developed and used to study the variation in polymer molar mass and molar mass distribution due to changes in the mode of polymerization. The potential of the method, which enables one to influence within certain limits the molecular weight distribution of a polymer prepared in a throughflow tubular reactor, is illustrated using the example of polyisobutylene.

This review examines the effect of the composition of polyreactive oligomers and of the type of reaction, on the kinetics of formation and the topology of crosslinked polymers, formed by the polyaddition and chain polymerization mechanisms, and on the microheterogeneity of network polymers and the mechanism of formation of polymer networks. A general phenomenological theory of network formation is proposed, on the basis of existing evidence relating to systems in which the rate of chain propagation is greater than the rate of branching. It proceeds from the concept of formation in the pre-gel period of colloidal particles of primarily branched macromolecules, which undergo intra- and intermolecular crosslinking, with formation in the first place of a dispersed phase and then of a continuously solid, microheterogeneous polymer, containing crosslinked aggregates interconnected by chains passing through more than one aggregate, by sparsely crosslinked zones or by regions of interpenetrating networks. In systems where the propagation and branching rates are similar, formation of more homogeneous network polymers is possible, giving better agreement between calculated (statistical) and experimental results. The proposed crosslinking mechanism is confirmed experimentally and used for predicting methods for control of the kinetics of crosslinking and of the structure and properties of crosslinked polymers.

Heat transfer at the gas-solid interface in degradation of polymers underconditions simulating the action of a flame has been investigated, and the heat of evaporation and temperature of the surface layers of the polymers (PMMA, PS, PE, PP and POM) were determined in the course of the work. Problems relating to the effect of the characteristics of the external medium (the composition and temperature of the gas) on these quantities are discussed. The energies of activation for pyrolysis of PMMA, PS and PE were determined.

The kinetics of radiation curing of bis-(methacryloxyethylene carbonato)-propanediol-1,3 (OCM-8) has been studied by the calorimetric method, both during irradiation and in post-irradiation polymerization. At degrees of conversion of 1–40% and dose rates of 0·4–15 rad/sec, the rate of polymerization of OCM-8 is proportional to the dose rate to the power of 0·9–1·0. In the low temperature region the energy of activation for polymerizations is weakly dependent on conversion ( E app = 13–20 kcal/mole). In the high temperature region E app = 2 kcal/mole at 1% conversion and at 40% conversion E app = 14 kcal/mole. As the OCM-8 is warmed up, immediately after its transition from the glassy to the supercooled liquid state vigorous post-polymerization occurs. Oxygen inhibits this polymerization only when the dosages of preliminary irradiation are low (0·005 Mrad). At dosages ⩾0·1 Mrad dissolved oxygen does not affect the rate of the post-effect.

A study was made of kinetics of synthesis of diane epoxide resins under conditions simulating advanced stages of the process. Synthesis was mathematically simulated bearing in mind reactions of crosslinking of oligomers and hydrolysis of epoxide groups. Velocity ratios of these reactions were determined depending on solvent composition. It was shown that oligomer structure depends on the velocity ratio of these reactions. The degree of branching of oligomers may be controlled by carrying out synthesis in a corresponding solvent.

The kinetics of the polymerization of methyl methacrylate (MMA) and dimethyltriethylene glycol (TGM-3) have been studied in the presence of oxygen and of an anti-oxidant (AO). The induction period depends on the monomer concentration in a closed system and increases with the AO content only in a relatively narrow range of concentration. A method is suggested for estimating the initiation rate of the polymerization. The ratio of the rate constant of the phenol inhibited reaction to that of a peroxide radical reaction with the monomer has been evaluated. The solubility of oxygen in MMA and TGM-3 has been determined.

The authors have studied the effect of pressure p of up to 2·5 × 103 MPa on the dielectric constant e and conductivity G of a number of iodine-doped polymers with a conjugation system. They have investigated polyphenylacetylene obtained on iron acetylacetonate, polyphenylacetylene obtained on a Ziegler catalyst, anionic polytolane and polyphenylbutadiine. It was found that after doping the values of e and G rise and begin to depend closely on p. The possible mechanism of this phenomenon is discussed.

Control of molecular weight characteristics of a polymer product is of special importance in the case of fast and ultrafast polymerization processes (kp⩾105 1./mole·sec) such as polymerization of isobutylene, vinyl butyl ether etc. The width of the molecular weight distribution of the product, in particular of polyisobutylene, reflects the non-uniformity of the temperature field in the reaction zone. Polyisobutylene can however be polymerized under nearly isothermal conditions in a cascade of tubular reactors, each provided with a separate, continuous supply of initiator, if an efficient external heat exchange is ensured.

Simple and complex ionic radical salts of tetracyanquinodimethane (TCQM) were produced with a number of polymers belonging to 3 different classes, i.e. those with a saturated main chain, with a conjugated system and with a nitrogen atom in the main chain. The effect of the polycation, the specific activity of the ionic radical and the physical and chemical properties of the salts formed were examined. Their catalytic or inhibiting activities were tested in the oxidation of cumene and in the thermal-oxidative degradation of polyorganosiloxanes.

A study was made of the crystalline structure of α, μ-bis-(4-methacryloxyethyl carbamate toluylene-2-carbamic) esters of oligoethylene glycols of different molecular weights and crosslinked polymers therefrom. The first members of oligomer homologues are crystalline substances with a molecular lattice typical of individual compounds. Oligomers with M n ⩽1200 are amorphous. All polymers prepared from oligomers with M n ⩽1200 are amorphous. Both oligomers and polymers with a dimension of the oligomer unit corresponding to M n ⩾2000 ( n ⩾60) form crystals with structures similar to the structural group of the initial oligoethylene glycols. Crystallinity in both cases increases with the dimension of the oligomer unit and reaches a limiting value when M n ⩾3600 ( n ⩾60).

The relative stability of various groups present in PVC molecules was calculated by means of the MO-LCAO method. It has been shown that the presence of carbonylallyl (−C(O)−CH=CH−CHCl−) and polyene (−CH=CH)n− groups is the main reason for the low thermal stability of the polymer. The formation of short polyene sequences, −C(O)−(−CH=CH−)n−CHCl− (n=2,3), is initiated by carbonylallygl groups already at relatively low temperatures of 273–413 K.

A new general method was developed for the synthesis of tetracarboxylic acid dianhydrides. The method involves the Diels-Alders reaction between maleic anhydride and bis-furan compounds and subsequent aromatization of the adducts formed. Using the dianhydrides obtained poly-(aroylene-bis-benzimidazoles) and polyimides were synthesized by single- and two-stage methods. The polymers are stable in air up to 500–550° and with lateral phenyl substituents are soluble in organic solvents. When the polymers are synthesized in polyphosphoric acid the stage of aromatization of adducts is excluded.

The optimum conditions have been found for polymerization of oligocarbonate methacrylates based on glycols with an odd number of carbon atoms of normal and iso-structure. The morphology and some mechanical properties of three dimensional polymers based on the oligocarbonate methacrylates have been investigated. The polymers are characterized by a microheteroglobular structure, which is responsible for their relatively low strength properties.

Results are given of determining molecular characteristics of polyisobutylene using a combination of a liquid chromatograph and a double bond analyser (ADS-4). The possibilities offered by the method are compared with those well known for determining MW and MWD of polyisobutylene.

The patterns of thermocatalytic degradation of polyisobutylene have been studied in presence of complex salts of the Me[AlCl4] type where Me is Li, Na or K. A special feature of the degradation in presence of salts is change in the character of initiation depending on the nature of the metal, the M of the polymer and temperature.

Conjugated dienes are shown to gave a stabilizng action on the thermal dehydrochlorination of PVC associated with saturation of  C = C  bonds in labile C(O) CH=CH groups This follows a Diels-Alder reaction, thus eliminating their stabilizing influence on the decay of neighbouring vinyl chloride units. The kinetics of dhydrochlorination of PVC modified by conjugated dienes have been investigated along with features of the thermal degradation of PVC in the presence of dienes. These features are related to the equilibrium chracter of the diene synthesis reaction.

A study was made of molecular mobility in crosslinked polymers obtained by hardening of dimethacrylic esters of oligotetramethylene glycols of different molecular weights. Several relaxation transitions were detected by dynamic mechanical methods which are determined by the dimensions of oligomer units. Starting from a given length of the unit, segmental mobility was observed in oligotetramethylene oxide units, as well as segmental motion in the main poly-methacrylate chains.

It is shown that the copolymerization of elastomers with oligo(acrylic esters) leads to uniform distribution of hardened OEA phase in a matric of the studied rubbers (SKN-26M, SKMS-30-ARK, SKEP). The OEA phase is in the form of separate inclusions with narrow scattering in respect to size. The average size of these localized micro-regions has been determined.

The influence of high pressure and shear strain on conductivity G and capacitance C of non-metallic polyphthalocyanines with different macromolecule lengths and degrees of crosslinking have been studied. Both the G and C of the polymers was found to increase with compression. Similar phenomena were observed during the simultaneous action of high pressure and shear strain on the polyphthalocyanines (PPC). However, in the latter case, the change in G necessitates a lower pressure than for a single compression. Spectral studies show that the effect of pressure and strain of loaded samples on their electrophysical properties is not connected with the chemical structure of the PPCs, but is evidently due to a change in the average separation between regions of continuous conjugation. It was shown that the dimensions of these regions may be increased by preliminary thermal treatment of the PPC.

A mathematical analysis of the kinetics of the rapid polymerization of isobutylene has been made; this has been done with a continuous scheme in which the special features of the properties of the reaction medium and the technological parameters of the reaction behaviour are taken into account. It has been shown that rapid reaction with local introduction of the catalyst occur in separate zones as a “flame” with different temperatures and kinetic parameters: this is accompanied by the formation of a polymer with enhanced molecular non-uniformity. The calculated data have been compared with experimental data and they have been found to agree.

The content of the internal bonds λ0 in the macromolecules has been calculated from change in the mean viscosity molecular mass of PVC on ozonization of the bonds taking into account the MMD and the number of internal bonds in the macromolecules of the polymer. Mathematical relations are derived for calculating λ0 for monodisperse (Mw/Mn=1), narrow (1 2) MMDs of PVC. The content and distribution of the unsaturated bonds in the initial, fractionated PVC samples and in the copolymers based on vinyl chloride have been evaluated. It is shown that the character of the distribution of the bonds in the macromolecule changes with the conditions in which the polymers are obtained.

The relaxation properties of a number of polynaphthoylenebenzimidazoles have been investigated and the regions in which the mechanical properties of the polymers may be used have been investigated. These systems have high glass transition temperatures that coincide with the temperatures for the start of intense thermal degradation. It has been shown that particles of polynaphthoylenebenzimidazole powders have a high auto-adhesion so that solid specimens may be formed from them over a wide range of temperatures and pressures.