Tailoring Molecular Weight of Polymer Additives for Organic Semiconductors

A binary system comprising both an organic semiconductor and a polymer additive has attracted extensive research interests due to great potential for high-performance, solution-proccessable electronic devices on flexible substrates. The...

Effect of Polymer Additives on the Microstructure and Mechanical Properties of Self-Leveling Rubberised Concrete

The materials based on concrete with an addition of rubber are well-known. The interaction between concrete components and rubber particles is in the majority cases insufficient. For this reason, different substances are introduced into concrete-rubber systems. The aim of this paper is to establish the influence of five different polymer additives, i.e., 1. an aqueous dispersion of a styrene-acrylic ester copolymer (silanised) (ASS), 2. water dispersion of styrene-acrylic copolymer (AS), 3. anionic copolymer of acrylic acid ester and styrene in the form of powder (AS.RDP), 4. water polymer dispersion produced from the vinyl acetate and ethylene monomers (EVA), 5. copolymer powder of vinyl acetate and ethylene (EVA.RDP)) on the properties of the self-leveling rubberised concrete. Scanning electron microscopy has allowed to establish the interaction between the cement paste and rubber aggregates. Moreover, the compressive strength and flexural strength of the studied materials were evaluated. The results indicate that the mechanical properties depend extensively on the type as well as the amount of the polymer additive introduced into the system.

EVALUATION OF TECHNOLOGICAL PARAMETERS OF ASPHALT CONCRETE MIXTURES FOR THE STREET-ROAD NETWORK IN URBAN AGGROMERATIONS USING ADDITIVES OF POLYETHYLENE WITH LOW MOLECULAR WEIGHT

Получены значения динамической вязкости битумного вяжущего с добавками низкомолекулярного полиэтилена в температурном интервале 60…160 °С. При введении полимерных добавок в дорожный битум вязкость битума повышается. Наиболее высокие значения динамической вязкости наблюдаются у полимерной добавки Вискодор - ПВ1, это ярко выражено при расходе 4 % добавки от массы битума и при температурах ниже 130°С. Добавка неокисленного низкомолекулярного полиэтилена Honeyvell Titan 7205 увеличивает вязкость в большей степени, чем добавка окисленного полиэтилена Honeyvell Titan 7686. Определены допустимые технологические температуры асфальтобетонных смесей с полимерными добавками на этапах структурообразования асфальтобетона. We obtained the values of the dynamic viscosity of bitumen binder with additives of polyethylene with low molecular weight in the temperature range of 60…160 °C. When polymer additives are introduced into road bitumen, the viscosity of bitumen increases. The highest values of dynamic viscosity are observed for the polymer additive Viskodor - PV1, this is clearly pronounced at the consumption of 4 % of the additive based on the mass of bitumen and at temperatures below 130 °С. The additive of unoxidized low molecular weight polyethylene Honeyvell Titan 7205 increases the viscosity to a greater extent than the additive of oxidized polyethylene Honeyvell Titan 7686. We determined as well the permissible technological temperatures of asphalt concrete mixtures with polymer additives at the stages of structure formation of asphalt concrete.

Synthesis and characterization of alkyl-methacrylate-maleic anhydride copolymer for use as a biodiesel flow improver

Methacrylic acid was esterified with four alcohols: 1-decanol, 1-dodecanol, 1-tetradecanol, and 1-cetanol. Afterwards, the obtained monomers were copolymerized with maleic anhydride. The synthesized monomers and copolymers were characterized by 1H-NMR (Nuclear magnetic resonance) and Fourier transform infrared (FTIR) spectroscopy. The ability of the obtained copolymers to reduce the pour point of waste cooking oil-based biodiesel was investigated. The results showed that the polymer additive with the alkyl chain C14H29- demonstrated the best flow improvement performance. At a concentration of 1000 ppm, this polymer additive reduced the pour point of waste cooking oil-based biodiesel from 12 to 5oC.In this study,the effect of alkyl chain length, molecular weight, as well as the concentration of the additives on the pour point of biodiesel was also discussed.