The ability to predict polymer properties from a knowledge of the chemical architecture of the chains is one of the main goals of polymer science, and achievement of this can be very useful in the development of new polymeric materials. In this paper the connection between dimensions of polyolefin chains and some of their most fundamental properties, such as the degree of entanglement and misci...

This study presents a study on the ductility performance of hybrid fibre reinforced concrete. The influence of fibre content on the ductility performance of hybrid fibre reinforced concrete specimens having different fibre volume fractions was investigated. The parameters of investigation included modulus of rupture, ultimate load, service load, ultimate and service load deflection, crack width...

The large variation in miscibility of blends of polyolefins is related to the architecture of the chain molecules. In this paper we present first results of an approach in which small scale simulations of local interactions are combined with an analytical model for the thermodynamics, the Born-Green-Yvon lattice model, to predict phase diagrams of polyolefin blends from the pure component prope...

BACKGROUND Molar bonding procedures need continuous improvement to be widely accepted clinically and eventually replace molar bands. MATERIAL AND METHODS The purpose of this study was to determine the effects of enamel micro-abrasion and silane coating of the base of molar tubes on shear and tensile bond strengths of orthodontic molar tubes. A total of 200 third molars were randomly allocated...

OBJECTIVES To evaluate the effect of different silane agents and air-drying temperatures on bond strength of translucent quartz fibre posts to composite resin. METHODS The post surface was etched with 10 vol% hydrogen peroxide for 20 min. A two-liquid coupling agent containing 4-methacryolxyethyl trimellitate anhydride (4-META) and gamma-trimethoxysilyil propyl methacrylate (gamma-MPTS) and t...

The aim of this study was to evaluate the influence of ceramic surface treatments and silane drying temperature on the microtensile bond strength (µTBS) of a resin composite to a lithium disilicate ceramic. Twenty blocks (7x7x5 mm) of lithium disilicate-based hot-pressed ceramic were fabricated and randomly divided into 4 groups: G1: acid etching with 9.5% hydrofluoric acid for 20 s and drying ...

OBJECTIVE To evaluate the effect of five experimental silane monomer primers in vitro on the shear bond strength of a phosphate ester resin-composite cement bonded to a silicatized zirconia framework. METHODS A total of 144 planar zirconia (Procera AllZircon) specimens were subjected to tribochemical silica treatment, randomly divided into 12 sub-groups (n=12), and silanized with 1.0%(v/v) ac...

An investigation of Thapsia garganica afforded a series of tetracyclic C-19 dilactones, whose production was dependent on the time and location of the collection. These unusual tetrahomosesquiterpenoids are presumably biosynthesized via a carbon dioxide-triggered electrophilic polyolefin cyclization. Despite the structural differences with thapsigargin, these compounds showed SERCA-inhibiting p...

We present a theoretical approach which maps polymer blends onto mixtures of soft-colloidal particles. The analytical mesoscale pair correlation functions reproduce well data from united atom molecular dynamics simulations of polyolefin mixtures without fitting parameters. The theory exactly recovers the analytical expressions for density and concentration fluctuation structure factors of soft-...

As a significant part of municipal solid waste (MSW), waste cardboard (CB) is a sustainable, inexpensive, and rich source of cellulose. Previous studies of polyolefin/CB composites have reported modest enhancement to major reduction in modulus and major reduction in elongation at break values relative to neat polymer. Here, green hybrids of low density polyethylene (LDPE) and polypropylene (PP)...