Development of mathematical model of curing two-phase polymeric systems

During research of kinetics of curing of two-phase elastomeric composites the new kinetic model, allowed to explain heterogeneity of the grid which was formed in this process of curing crosslink was developed. In numerical experiments it is shown that average extent of sewing together of all system increases more slowly, than when curing in lack of diffusion of vulcanizing substances, and the speed of curing and the general extent of sewing together of a composite as a whole decreases

On thermo-fluctulation description of chemical reactions in polymers

Investigations of polydienes with various chemical structures and microstructures were carried out, and interrelations of molecular-structural characteristics of polydienes with their macroscopic properties in thermo-oxidation processes were shown. An experimental-formal approach to substantiation of cross-linking and destruction depth of carbon-chain linear polydiene macromolecules is proposed. The extrapolation value of the molecular weight of the chain ensuring activation of chemical reactions of vulcanization and oxidation was obtained. It is proposed to use the criterion of destruction for calculating the number of chain splinters resulting from macromolecule ruptures

Influence of mineral carrier type in the structure of composite vulcanization activator on the properties of molded rubber

Properties of the rubber mixtures and vulcanizates based on styrene-butadiene rubber composition in the presence of composite vulcanization activator were studied. Activators include zinc oxide, fatty acids and derivatives thereof, mineral fillers and organic fillers. It has been established that the use of new activator provides the desired cure rate. By the level of elastic and strength properties of prototypes to meet or exceed the standards of control. The possibility of reducing the dosage of vulcanization activators while maintaining the required level of vulcanization and physical-mechanical properties of molded rubber. Advantage of advanced products is the ability to reduce the content of environmentally hazardous zinc oxide formulations rubber goods and improved manufacturing techniques of rubber compounds through the use of non-dusting forms of ingredients

Butadiene-styrene thermoplastic elastomer with special properties

Structure and rheology of thermoplastic elastomers with stiff links of styrene in polybutadiene unit are examined. Molecular and structural characteristics TPE withthe high vinyl links of polybutadiene are shown. Structure and technological properties of the thermoplastic elastomers modified in the synthesis stage are compared

Simulation of polidiene oxidation kinetics

Synthetic isoprene rubber (SIR) is similar in structure and to the properties of natural rubber (NR). Currently, it can almost completely replace NR in the production of automobile tires and rubber products. An urgent task is to study the aging processes of polymers and their products, assess the impact of various factors on the oxidative stability of polymers and the selection of effective ways to protect polymers from aging. We simulated aging of inhibited (commodity) and reprecipitation (purified) polyisoprene

Modeling of kinetics of nonisothermal vulcanization of massive rubber products

The problem of vulcanization (curing) of massive products is considered important for technology of processing of polymers. It is shown, that during structurization compound rubber materials distribution of temperatures on all section is unequal, that results in distinction in structure and properties of such samples. Temperature fields in cuts of a product are designed and dependences of change of structural parameters are established. Kinetic characteristics of process of vulcanization are determined and recommendations on creation and updating of modes of vulcanization massive elastomer products are produced

Infuence of processing conditions of polymethyl methacrylate on the optical and mechanical propeties of products

Study of the mechanical and optical properties of PMMA, including the addition of recycled materials, have been conducted. the possibility of using recycled materials in the manufacture of products made of PMMA was shown. Found that the optical properties deteriorate with the introduction of secondary PMMA over 10%

Features of rubber crosslinking in the presence of composite vulcanization activators

The features of curing polydienes by vulcanizing system based on composite curing activators was studied. Based on analysis of the investigating results of cure and elastic-strength properties rubbers was found that the modification of zinc oxide as a basis of the formation of actual curing agents increases of the active sites of vulcanization and as a consequence, increases the rate of vulcanization and improving physical and mechanical properties of rubbers

Кинетика окисления полиизопрена в присутствии активных добавок

Analysis of changes in the structure and properties of polyisoprene films was carried out. The samples contained chemically active additives (antioxidants, antiscorchings) and were subsequenly warmed up.Проведен анализ изменения структуры и свойств пленок полиизопрена, содержащих химически активные добавки (противостарители, антискорчинги) с последующим прогревом образцов

Элемент согласования волноводной линии передачи с диодом

The article deals with the issues of matching a waveguide transmission line with millimeter wave diodes. The implementation of the transition of a rectangular waveguide to a microstrip switching line in the form of a line of the fin-line type is described. The computer simulation results of the transmission coefficient module of the developed element and the standing wave coefficient by voltage separately for the transition from a rectangular waveguide to a microstrip transmission line and as part of an amplitude detector are shown. A joint application of the developed element with a microstrip detector based on a Schottky diode in the frequency range from 118.1 to 178.4 GHz is proposed. The results of measuring its parameters and the results of determining the sensitivity are given, as well as the evaluation of the results obtained is performed. The obtained results proved the possibility of using the matching element of a waveguide transmission line with a diode in the millimeter wavelength range. Рассмотрены вопросы согласования волноводной линии передачи с диодами миллиметрового диапазона длин волн. Описана реализация перехода с прямоугольного волновода на микрополосковую линию передачи в виде линии типа фин-лайн. Показаны результаты компьютерного моделирования модуля коэффициента передачи разработанного элемента и коэффициента стоячей волны по напряжению отдельно перехода с прямоугольного волновода на микрополосковую линию передачи и в составе амплитудного детектора. Представлена реализация совместного применения разработанного элемента с микрополосковым детектором на базе диода Шоттки в диапазоне частот от 118,1 до 178,4 ГГц. Приведены результаты измерения его параметров и определения чувствительности. При оценке полученных данных подтверждена возможность применения разработанного элемента согласования волноводной линии передачи с диодом в миллиметровом диапазоне длин волн