Key Engineering Materials Vol. 869

Abstract: The reactivity of 3,5-di-tert-butyl-o-benzoquinone and its bis-o-benzoquinone derivative in photoreduction reaction and polymerization of dimethacrylate (OCDMA) (in bulk and in the presence of 1-butanol) with using of them as photoinitiators under visible light irradiation under argon atmosphere or air were investigated. It was found that the kinetic parameters of the bis-o-quinone photoreactions have low sensitive to the presence of molecular oxygen. The high stability of the spectral characteristics of resulting polymers based on bis-o-quinones compositions for the long time was established.

Abstract: The results of experimental studies of the composition of individual substances migrating from medical rubber plugs produced both in and abroad based on technical bromobutyl rubber are presented. The quantitative content of volatile organic compounds related to species impurities of gasoline was determined by gas chromatography from a standard glass bottle sealed with a sterile stopper based on bromobutyl rubber. The method of atomic emission spectroscopy was used to determine (indirect) the presence of organometallic, organosulfur and metal-inorganic compounds that did not pass through chromatographic columns, and the presence of organometallic, organosulfur and metal-inorganic compounds was determined by the content of metal and non-metal cations. The results of mass spectral studies of extracts of aqueous extracts from plugs based on bromobutyl rubber showed that they contain impurities of bromo-alkanes and bromo-arenes, which are direct-acting carcinogens.

Abstract: The effect of polyketone thermal processing duration on the rheological properties of the melts and the physical and mechanical characteristics of the samples, obtained by injection and compression molding methods, is studied.

Abstract: Composite binders (CB) for road construction, based on bitumen and active powder of discretely devulcanized rubber (APDDR), obtained by the method of high-temperature shear grinding (HTSG), are considered. The formation of CB occurs with the introduction of APDDR in bitumen during the preparation of the asphalt mixture. The advantages of CB compared with bitumen in a wide temperature range are shown: a decrease in plastic deformations at high temperatures, an increase in fatigue life and resistance to the formation of low-temperature cracks.

Abstract: It is proposed to synthesize one-component light-resistant urethane compositions using aldimines as crosslinking agents and methyl iodide as an activating agent to obtain sealants. The effect of the methyl iodide activator and the quaternized complex of the imine group and temperature on the cure time of the sealants was investigated. The influence of the polyether molecular weight and the structure of aldimines fillers on the physical and mechanical properties of the obtained sealants was studied.

Abstract: The rubber compounds based on BR and on mixtures BR with EPDM containing experimental organoclay samples based on bentonites from the “Sarinskoye” deposit (Orenburg Region, Russia), additives to polymers Cloisite® 10A manufactured by Southern Clay Prod. () were compared. The increase of tensile strength at break by introduction of organoclay in rubber compounds based on BR and on mixtures BR with EPDM was determined. The compatibility of rubbers with the introduction of organoclay in the mixture BR with EPDM was improved

Abstract: The “cross-linked” copolymers based on styrene, divinylbenzene, and functionalizing monomers namely ethylene glycol dimethacrylate and liquid hydroxyl terminated polymer of butadien Polybd® R-20 LM Resin by miniemulsion polymerization in the presence of a co-stabilizer – hexadecane were prepared. The largest copolymer yield for both functionalizing monomers by amount of hexadecane 5 % wt. was achieved. The industrial latex SKS-30 ARKM-15 by the obtained copolymers in the process of salt coagulation was modified. The mechanical characteristics of vulcanizates made on the basis of rubber SKS-30 ARKM-15, modified by obtained copolymers were studied.

Abstract: We are the first to report the synthesis of maleic acid in quantitative yield by oxidation of 5-hydroxymethyl furfural with hydrogen peroxide in the presence of sodium bicarbonate in an aqueous medium under ambient conditions without the using of toxic catalysts and solvents. 5-hydroxymethyl furfural and 2,5-furandicarboxylic acid have been prepared from hexose plant biomass. Based on maleic anhydride and 2,5-furandicarboxylic acid, unsaturated polyesters were synthesized for the first time from renewable raw materials only. A fiber-reinforced polymer composite based on these polyester resins have been prepared. Strength properties of carbon and glass fiber-reinforced polymer composites are 1.5 times superior to the strength of similar phthalic acid based composites.

Abstract: For the first time, the possibility of synthesis of 2,5-furandicarboxylic acid (FDCA) and 5,5-oxy-bis (methylene) bis-furane-2-caboxylic acid (OBFA) diesters and using them as plasticizers of various polymers have been studied. The most effective method for the synthesis of furan diesters is the direct esterification of FDCA or OBFA with the corresponding aliphatic diols С₄-С₁₀. Methods for the synthesis of these diesters with the yield of the target product from 45 to 85 % have been developed. The physical properties and plasticizing ability of the obtained 14 diesters were investigated. The plasticizing ability of the obtained diesters with respect to polyvinyl chloride (PVC), polystyrene (PS) and polymethyl methacrylate (PMMA) was studied. The plasticizing effect depends on the chain length of the aliphatic diol and the nature of the polymer. In general, the synthesized diesters have a stronger plasticizing effect on PS than on PVC and PMMA due to the higher stiffness of the PS chain. The plasticizing ability of the synthesized furan diesters that can be obtained from renewable plant materials is slightly inferior to industrial plasticizers based on phthalic and adipic acids, and are potentially able to replace standard plasticizers derived from hydrocarbons.

Abstract: A wide range of membranes (hydrophobic and hydrophilic) for the task of triethylene glycol dehydration by thermopervaporation was studied. The transport characteristics of the membranes using individual liquids (water, triethylene glycol) were determined in the thermopervaporation process with varying temperature of the feed flux (40-). The maximum water flux (3.7 kg/m²∙h) in all the studied temperature ranges was demonstrated by the commercial pervaporation hydrophobic PolyAn membrane. For the commercial hydrophilic membrane MDK-I water flux at 80 °С was 2.8 kg/m²∙h. During thermopervaporation of triethylene glycol in the studied temperature range, TEG flux through the membranes was not observed, which shows the advantage of this process for TEG dehydration. For the first time, experiments were provided using PolyAn membranes to removal water from TEG by thermopervaporation with porous condenser. The maximum permeate flux (1.9 kg/m²∙h) was achieved for the PolyAn membrane at a concentration of 70 % wt. TEG in water