Mechanical and thermomechanical properties of highly basic anion-exchange fibres based on polypropylene containing grafted-on polystyrene

Conclusion The dependence of the mechanical and thermomechanical properties of fibres from polypropylene containing grafted polystyrene and of the anion-exchange fibres based on them on the content of grafted polystyrene in the fibre has been examined.It has been shown that the observed decrease in strength and elastic modulus of the original polypropylene fibre on grafting polystyrene and subsequent polymer-analogous transformations of it is entirely caused by an increase in linear density of the fibres.The animated polystyrene grafted to the polypropylene ensures an increase in the softening point of the anion-exchange fibres of 80 to 100°C as compared with the softening point of the original polyproplene fibre.Translated from Khimicheskie Volokna, No. 4, pp. 28–30, July–August, 1985.     

Calcium Silicate Hydrates Studied by Small-Angle Neutron Scattering (SANS)

Small-angle neutron scattering (SANS) was used to study calcium silicate hydrate (C-S-H) formed via pozzolanic reaction between calcium oxide and ultrafine silica in water or polymer solutions at a temperature of 20°C. The SANS profile of this product was consistent with a structure that consisted of platelets with maximum diameters of ∼20 nm (± 5 nm) in the x – y plane, which was similar to a structure that had been deduced in previous work via X-ray diffractometry. The presence of two different types of superplasticizer in solution (at a concentration of 10 g/L) had no significant effect on its formation kinetics or its SANS profile.     

Development of New Generation Ceramics for Their Potential Use in Domestic Industries

A brief survey of four groups of ceramic materials with a potential for effective use in science and technology is given. Durable ceramics based on Al₂O₃ and ZrO₂ are considered and areas of application are outlined. Corundum ceramics using eutectic additives that allow the sintering to be conducted at lower temperatures are discussed; structural features and properties of new materials and areas of application are considered. The use of porous ceramic materials for filtering cells and catalyst carriers is discussed. Bioceramics with a dense and porous structure based on hydroxyapatite that find ever-increasing interest for use in medicine are considered.