Vallittu P K
University of Turku, Institute of Dentistry, Department of Prosthetic Dentistry, and Biomaterials Project, Finland.
J Oral Rehabil. 1998 Feb;25(2):100-5. doi: 10.1046/j.1365-2842.1998.00235.x.
The aim of this study was to determine the tensile strength and E-modulus of unidirectional denture glass fibre-polymethyl methacrylate (GF-PMMA) composite with various fibre contents. The experimental values of tensile strength and E-modulus were compared with values obtained by a theoretical calculation. Autopolymerized PMMA test specimens (n = 6, per group) were reinforced with unidirectional E-glass fibres which had been wetted in a mixture of PMMA powder and monomer liquid. After storing the test specimens for 40 days in water at 37 degrees C, the tensile strength and E-modulus of the test specimens were measured. The increased amount of fibres in the PMMA matrix (up to 14.8% by weight) increased the mean tensile strength of the test specimens from 40.5 MPa to 91.2 MPa (P < 0.001) and the E-modulus from 2057 MPa to 3751 MPa (P < 0.001). The experimental tensile strength and Emodulus values were considerably lower than those based on the theoretical calculations. This was assumed to be due to the percentage of glass fibres unimpregnated with the PMMA resin. The presence of unimpregnated glass fibres was determined using light microscopy. The results of this study suggest that a new method of incorporating the glass fibres into the PMMA resin matrix should be developed in order to obtain a well-impregnated fibre composite reinforcement with high durability.
本研究的目的是测定不同纤维含量的单向义齿玻璃纤维 - 聚甲基丙烯酸甲酯（GF - PMMA）复合材料的拉伸强度和弹性模量。将拉伸强度和弹性模量的实验值与理论计算得到的值进行比较。用在PMMA粉末和单体液体混合物中浸湿的单向E玻璃纤维增强自凝PMMA测试样本（每组n = 6）。在37℃水中将测试样本储存40天后，测量测试样本的拉伸强度和弹性模量。PMMA基体中纤维量的增加（重量比高达14.8%）使测试样本的平均拉伸强度从40.5MPa增加到91.2MPa（P < 0.001），弹性模量从2057MPa增加到3751MPa（P < 0.001）。实验测得的拉伸强度和弹性模量值明显低于基于理论计算的值。这被认为是由于未被PMMA树脂浸渍的玻璃纤维的百分比所致。使用光学显微镜确定未浸渍玻璃纤维的存在情况。本研究结果表明，为了获得具有高耐久性的良好浸渍纤维复合材料增强体，应开发一种将玻璃纤维掺入PMMA树脂基体的新方法。
