Study on properties of PB-g-PS latex-modified cement mortars
The PB-g-PS latex was used to modify cement mortar, and the weight ratios of polybutadiene to styrene ranged from 70/30, 50/50 to 30/70. In the constant water-cement ratio of 0.5, and curing 24h at 20°C, RH90% air followed by 27d at 20°Cwater. This study examines the effects of weight ratios polybutadiene to styrene and the polymer-cement ratios on the flow, compressive and flexural strength and water absorption rate of PB-g-PS latex modified cement mortar. The experimental results show that the flow of modified mortar is increased with increasing polymer-cement ratios and decreasing weight ratios of polybutadiene to styrene, PB-g-PS latex can markedly reduce capillary water absorption rate. The minimum is 1.33Kg/m2. PB-g-PS latex can marked influences much on the mechanical properties of modified mortars. The compressive of the polymer modified mortar decreased, and the flexural strength of polymer modified mortar decreased as well. Overview on, PB-g-PS latex can be incorporated into cement mortars as cement modifier.
Mechanical characterization of a styrene–butadiene modified mortar
Abstract Polymer-modified mortars (PMCs) are used in the construction industry as tile adhesives or frontage coatings. This way of modifying classical mortars improves practical use and adhesion properties. However, the influence of the polymer phase on the durability and the mechanical properties of the modified mortars are still unknown. Three-point bending and compression tests were carried out on PMCs and classical mortar beams. The tests were made under strain control in order to reach the softening part of the stress–strain curve. The compression tests show the influence of polymer content on elastic characteristics, mechanical resistance and strain at rupture. Three-point bending tests reveal the PMC behavior in tension and the damage evolution is monitored by the loss of stiffness. Finally, scanning electron microscopy shows the polymer distribution in the composites.
EL TRATAMIENTO NEOPRAGMATISTA DE LA VERDAD EN RICHARD RORTY NEOPRAGMATIST TREATMENT OF TRUTH IN RICHARD RORTY
Richard Rorty, one of the most influential authors of our time, presents a critique of the philosophical concept of truth as correspondence. The conclusion of Rorty's neopragmatism is that the idea of truth as correspondence between language and facts is ineffective because it no longer works. The neopragmatist conception of truth indicates the only possible uses for the term «truthful,» revolving around the idea of jus - tification. In this article, the neopragmatist notion of truth is presented in order to