硅烷偶联剂及浓度对纤维增强牙科复合材料断裂韧性和吸水性的影响。

Effect of silane coupling agent and concentration on fracture toughness and water sorption behaviour of fibre-reinforced dental composites.

机构信息

School of Mechanical and Manufacturing Engineering, University of New South Wales, NSW, 2052, Australia.

School of Mechanical and Manufacturing Engineering, University of New South Wales, NSW, 2052, Australia; Division of Applied Oral Sciences & Community Dental Care, Faculty of Dentistry, University of Hong Kong, Hong Kong, China.

出版信息

Dent Mater. 2023 Apr;39(4):362-371. doi: 10.1016/j.dental.2023.03.002. Epub 2023 Mar 13.

DOI:10.1016/j.dental.2023.03.002

PMID:36922257

Abstract

OBJECTIVES

This paper presents the effect of silane treatment of S-2 Glass fibres on the fracture toughness and water sorption/solubility behaviour of fibre-reinforced flowable dental composites. The effect of epoxy- and methacrylate-based silane coupling agents (SCAs) on the mechanical strength and hydrolytic properties were investigated. The concentration of the selected SCAs on the mechanical and physical properties were investigated. The influence of molecular structure and concentration in the interfacial adhesion at the fibre-matrix interfaces was also studied.

METHODS

Short S-2 Glass fibres of 250 µm in length and 5 µm in diameter were etched with acid to remove any impurities and roughen the surface. The acid-etched fibres were silane treated with 3MPS, 3GPS, and 8MOTS at different concentrations by weight (%). The silane-treated fibres were incorporated at 5 % into the dental resin mixture. Untreated fibres were added at 5 % to the dental resin mixture and served as the control group. The physical properties such as water sorption, solubility, and desorption along with mechanical properties such as fracture toughness and total fracture work of the fibre-reinforced dental composites grafted with the above-mentioned SCAs were evaluated. The surface morphology of the fractured surface was studied and analysed.

RESULTS

The fracture toughness tests showed that the dental composites grafted with optimum weight per cent (wt. %) concentration of the SCA had a better stress intensity factor (K) when compared to the 2.0 wt. % and 3.0 wt. % concentration. The K value of dental composites grafted with untreated surface etched glass fibres was less than the K values of dental composites grafted with optimum concentrations of 3MPS, 3GPS, and 8MOTS by 81.6 %, 38.6 %, and 110.5 %, respectively. A similar trend was found while investigating the total work of fracture of the dental composites, between optimum concentration, 2.0 wt. % and 3.0 wt. % concentration of respective SCA. The increase in silane concentration also led to an increase in the water sorption/solubility characteristics. The absorption of water was most severe in the fibre-reinforced dental composites without silane treatment (32.9 µg/mm). The ANOVA results showed that the fibre-reinforced dental composites grafted with 8MOTS at optimum concentration showed an increase in fracture toughness when compared to optimum concentrations of 3GPS and 3MPS by 51.9 % and 15.9 %, respectively. The enhanced mechanical and physical characteristics are due to the increased adhesion between the fibre and silane achieved from the optimum wt. % concentration of 8MOTS. Similarly, dental composites grafted with 8MOTS at optimum concentration showed a decrease in water sorption characteristics when compared to optimum concentrations of 3GPS and 3MPS by 18.2 % and 0.6 %, respectively. The decreased water sorption characteristics at the optimum concentration of 8MOTS could be due to the reduced availability of reactive hydroxyl groups and the hydrophobic characteristics of 8MOTS.

SIGNIFICANCE

Silane coupling agents (SCAs) are important components of dental composites. The type and concentration of SCA have a significant effect on material properties. The current study focuses on understanding the effects of different SCAs and wt. % concentrations on the interfacial fracture behaviour and the influence of different SCAs on the water sorption and solubility behaviour of S-2 Glass fibre-reinforced flowable dental composites.

摘要

目的

本文研究了硅烷处理 S-2 玻璃纤维对纤维增强可流动牙科复合材料的断裂韧性和吸水性/溶解度行为的影响。研究了环氧和甲基丙烯酰基硅烷偶联剂（SCAs）对机械强度和水解性能的影响。还研究了所选 SCAs 的浓度对机械和物理性能的影响。研究了分子结构和浓度在纤维-基体界面的界面粘附中的影响。

方法

将长度为 250 µm、直径为 5 µm 的短 S-2 玻璃纤维用酸蚀刻以去除任何杂质并粗糙表面。用 3MPS、3GPS 和 8MOTS 以不同的重量百分比（%）对酸蚀刻纤维进行硅烷处理。将处理过的纤维以 5%的比例掺入牙科树脂混合物中。将未处理的纤维以 5%的比例添加到牙科树脂混合物中作为对照组。评估了用上述 SCAs 接枝的纤维增强牙科复合材料的物理性能，如吸水性、溶解度和解吸性，以及机械性能，如断裂韧性和总断裂功。研究并分析了断裂表面的表面形态。

结果

断裂韧性测试表明，与 2.0wt.%和 3.0wt.%浓度相比，用 SCA 的最佳重量百分比（wt.%）浓度接枝的牙科复合材料具有更好的应力强度因子（K）。用未处理的表面蚀刻玻璃纤维接枝的牙科复合材料的 K 值小于用 3MPS、3GPS 和 8MOTS 的最佳浓度接枝的牙科复合材料的 K 值，分别为 81.6%、38.6%和 110.5%。在研究牙科复合材料总断裂功时，也发现了类似的趋势，即在最佳浓度、2.0wt.%和 3.0wt.%浓度的各自 SCA 之间。硅烷浓度的增加也导致吸水性/溶解度特性的增加。未经过硅烷处理的纤维增强牙科复合材料（32.9µg/mm）的吸水率最大。方差分析结果表明，用最佳浓度的 8MOTS 接枝的纤维增强牙科复合材料的断裂韧性与 3GPS 和 3MPS 的最佳浓度相比分别提高了 51.9%和 15.9%。增强的机械和物理特性是由于纤维和硅烷之间的粘附增强，这是由 8MOTS 的最佳重量百分比浓度实现的。同样，用最佳浓度的 8MOTS 接枝的牙科复合材料的吸水性特征与 3GPS 和 3MPS 的最佳浓度相比分别降低了 18.2%和 0.6%。在最佳浓度的 8MOTS 下，吸水性特征的降低可能是由于反应性羟基的可用性降低和 8MOTS 的疏水性特征。