Influence of the base and diluent monomer on network characteristics and mechanical properties of neat resin and composite materials

Abstract

This study evaluated the effect of the combination of two dimethacrylate-based monomers [bisphenol A diglycidyl dimethacrylate (BisGMA) or bisphenol A ethoxylated dimethacrylate (BisEMA)] with diluents either derived from ethylene glycol dimethacrylate (ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate) or 1,10-decanediol dimethacrylate (D3MA) on network characteristics and mechanical properties of neat resin and composite materials. The degree of conversion, maximum rate of polymerization and water sorption/solubility of unfilled resins and the flexural strength and microhardness of composites (after 24 h storage in water and 3 months storage in a 75 vol% ethanol aqueous solution) were evaluated. Data were analyzed with two-way ANOVA and Tukey's test (α = 0.05). The higher conversion and lower water sorption presented by BisEMA co-polymers resulted in greater resistance to degradation in ethanol compared with BisGMA-based materials. In general, conversion and mechanical properties were optimized with the use of long-chain dimethacrylate derivatives of ethylene glycol. D3MA rendered more hydrophobic materials, but with relatively low conversion and mechanical properties.

Influence of pre-heating and ceramic thickness on physical properties of luting agents

“…In general, WS is correlated to interaction with groups susceptible to hydrolytic degradation, such as ester (OC=O), ether (-O-), and hydroxyl (-OH) present in monomers, to the characteristic three-dimensional polymer network formed, or to penetration through the interfaces present between filler particles and matrix. 18,19 The increased temperature probably led to a small increase in CLD of the formed polymer, sufficient to increase its hydrophobic character, however, without significant effect on the other properties tested. Thus, the first hypothesis was partially accepted.…”

Chemical and Mechanical Properties of Experimental Dental Composites as a Function of Formulation and Postcuring Thermal Treatment

“…Although the composites for both direct and indirect use generally have similar properties, the effects of variation in composition, especially in experimental composites, are being thoroughly studied [ 2 – 9 ]. Thus, it is known that the size, shape, distribution, composition, and concentration of the filler content, as well as the ratio between the main organic compounds that constitute the matrix, can affect the values of important properties, such as hardness, fracture toughness, diametral tensile strength, flexural strength, and elastic modulus [ 5 , 7 , 10 – 15 ]. For durability in treatment, it is of the utmost importance that resins demonstrate appropriate mechanical behavior, which is directly linked to the degree of conversion of the polymer matrix, the monomer composition, the fraction of inorganic filler, and the size and type of filler particles [ 5 , 16 , 17 ].…”

Comparison of Different Restoration Techniques for Endodontically Treated Teeth

“…e mechanical properties of a product depend on the composition of the material. Filler content and filler properties are known to affect the mechanical properties of resin composites [35]. It is claimed that fibre-reinforced composites have sufficient flexural strength and modulus of elasticity against functional forces in the mouth [32].…”