The chemical durability and mechanical properties of a kind of alkali-proof basalt fiber BF-CMD-01 and its reinforced F46 epoxy resin matrix composites are presented. The basalt fiber was boiled in distilled water, sodium hydroxide and hydrochloric acid, respectively. Then the mass loss and strength change of the fibers were studied showing that the alkali resistance of the basalt fiber is better than acid resistance. The flexural properties and surface morphologies of the composites were investigated after being immersed in 8 kinds of chemical mediums for 15, 30 and 90 days. Due to the difference of basalt fiber resistance in two kinds of mediums, the composites corrosion behaviors differ greatly in acid and alkaline reactions. In acid mediums, the flexural strength and flexural modulus change in the same way. In alkaline mediums, the flexural modulus keeps close to the original value while the flexural strength declines gradually. Additionally, the mechanical properties of basalt fiber reinforced polymer (BFRP) and S-2 glass fiber reinforced polymer (GFRP) have been tested, and analyzed contrastively. The results show that the interface formed between basalt fiber and epoxy resin is better than that of glass fiber and epoxy resin.

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Phenolic foams reinforced with pristine and functionalized multiwalled carbon nanotubes (MWCNTs) were fabricated to develop fire‐resistant materials with improved mechanical properties. The influences of the contents of carboxyl multi‐walled carbon nanotubes (MWCNTs‐COOH) and of MWCNTs types on the compressive properties of the composite foams were investigated. The microstructure and detailed failure behavior of MWCNTs/phenolic composite foams were studied using scanning electron microscopy (SEM) and in situ quasistatic compression inside SEM, respectively. In addition, thermal performances were evaluated by thermogravimetric analysis (TGA) and vertical burning method. It is found that as heterogeneous nucleation agents, MWCNTs increase cell density and decrease cell size of the produced foams, and that as reinforcements located in cell walls, MWCNTs impart high strength and stiffness to brittle foams. Moreover, MWCNTs reinforced foams have higher thermal stability than raw foams and exhibit similar excellent resistance to flame, confirming the effectiveness of MWCNTs as stabilizers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1479–1488, 2013

Process simulation is of great importance in the development of processes for cost-effective fabrication of composite structures, particularly for thermoset matrix composites. For the simulation of autoclave or hot press process, it requires knowledge of the compaction behavior and the saturated transverse permeability of fiber reinforcements. In this paper, a simple method without any sophisticated equipment is shown, which can simultaneously measure the compaction curve and the saturated transverse permeability as a function of fiber volume fraction. The method was used to measure the properties of S-2 glass rovings and T700S carbon rovings prepregs. The effects of the impregnating fluid variety, the initial fiber volume fraction of prepreg, and the lay-up type on the compaction behavior were investigated. The transverse permeability was also studied as a function of fiber content for various lay-up types. The results indicate that Gutowski's compaction model and the modified Kozeny-Carman equation proposed by Gutowski, which are important input parameters for the resin flow model, can be used to adequately fit the experimental data. POLYM. COMPOS., 28:61-70, 2007.

For resin matrix composites, voids are common defects that can seriously deteriorate the properties of the composite parts. Thus, the elimination of voids is a crucial element in controlling the manufacturing process of composite parts. This article focuses on void formation originating from hygroscopic water for resin matrix composite laminates prepared with hot pressing process. The Kardos void formation model was developed to analyze the critical resin pressure for the initiation of voids, and the influencing factors were investigated experimentally to validate the modified model. It is found that resin pressure and gel temperature are the two key parameters to control void defects and that entrapped air in prepreg stacks must be considered in the void formation model. Furthermore, a simple method was established to measure the relationship between porosity and the processing parameters, and the void formation conditions of the resin and the prepreg stack were also studied. The theoretically predicted void formation conditions and the experimental results were compatible for the studied cases. These results are valuable for eliminating void defects, optimizing processing parameters, and enhancing the performance of composite parts.