Microstructure of glass fibre reinforced supersulphated cement

The microstructure of one and two year old grc made from Cem-FIL alkali-resistant glass fibres and supersulphated cement has been examined using the scanning electron microscope. The structure and composition of two year old samples of supersulphated cement hydrated in a CO₂ free atmosphere is also reported. Differences in the microstructure of these cement samples and the matrix phase of the fibre composites are related to the carbonation of the composite specimens.     

Preliminary investigations of the dimensional stability of super-critically carbonated glass fibre reinforced cement

The dimensional changes occurring during the super-critical carbonation of glass fibre reinforced cement (GRC) and its subsequent environmental exposure have been investigated. Sheet samples, with embedded stainless steel pins 200 mm apart, were fabricated and then subjected to super-critical carbonation. Test coupons were subsequently exposed to a range of environments including continuous immersion in water, cyclic wetting/drying and outdoor exposure. The super-critical carbonation process resulted in a slight expansion of GRC. This is contrary to the behaviour observed during natural carbonation where irreversible shrinkage normally occurs. Exposure to the various environments mentioned above showed that super-critically carbonated samples had much greater resistance to swelling and shrinkage than uncarbonated specimens. These observations are particularly significant in relation to the practical application of GRC in environments of fluctuating moisture content.     

玻璃钢的湿法成形工艺

本文介绍了以不饱和聚酯树脂和玻璃纤维布湿法卷制玻璃钢管的成形工艺,并在卷制玻璃胶片轴芯简体及玻璃钢防腐管道的实践中证明该工艺的可行性.     

Fracture of glass fiber reinforced cement

Fracture patterns produced when a crack advancing from a notch in cement paste intersected a Cem FIL-2 glass fiber strand placed perpendicular to it were studied. The specimens were small notched compact tension specimens that could be wedge loaded in the scanning electron microscope chamber using a wet cell. Four distinct cracking patterns were identified. In most cases the fiber caused a shift in the crack path and in some specimens, microcracking and separation of the crack into 2 to 4 branches were observed. The filaments maintained their continuity and bridged over the track. Similar tests with E-glass fibers after accelerated curing revealed brittle behavior in which the crack path was straight and many filaments were broken.     

A technique for showing microcracks in fibre reinforced cement

A resin impregnation and etching technique has been developed for showing fine cracks in Glass Reinforced Cement (G.R.C.) composite material. It has been found to be particularly useful in examining G.R.C. materials after testing (tensile, bend and impact tests) as well as for studying surface shrinkage cracking. Although developed for G.R.C. the technique could also be applied to other Portland Cement materials.     

Improvement of the durability of glass fiber reinforced cement using blended cement matrix

Blended cements prepared with two fly ashes were used as matrices in glass fiber reinforced cement (GRC) composites in an attempt to improve their durability. The hydrated matrices from the two blended cements investigated here had similar strength and composition. Both fly ashes reduced the Ca(OH)₂ content to the same extent but in both cases the pH level was only slightly reduced compared to the portland cement matrix. In spite of these similarities, the GRC prepared with one fly ash showed considerable improvement in durability while the other one had only a small positive effect. SEM observations indicated that the improved durability in one case was associated with modification in the microstructure of the hydration products deposited in between the glass filaments, resulting in a much more open structure compared to that of portland cement matrix or the other blended cement. It is therefore suggested that the potential of the blended cement matrix to improve the durability of GRC is associated with its ability to modify the microstructure of the paste at the glass interface. This characteristic is not necessarily related to the overall composition of the blended cement matrix and to the reactivity of fly ash with Ca(OH)₂.     

Microstructural characterization of short glass fibre reinforced polyethersulfone composites

To explore the effect of short glass fiber reinforcement (SGFR) on the mechanical properties of polyethersulfone (PES), microstructural characterization has been performed by positron lifetime technique. The free volume distribution of SGFR‐PES composites derived from CONTIN‐PALS2 program exhibits the narrow full width at half maximum (FWHM) indicates the strong interaction between polymeric chains of PES matrix and SGF. The positron lifetime parameters of SGFR‐PES composites are correlated with the mechanical properties viz., Tensile strength (TS), Young's modulus (YM) and elongation at break (EB). The decreased positron lifetime parameters, improved mechanical properties and reduced crystallinity of SGFR‐PES composites are attributed to the improved chemical and physical interaction between the functional groups of both SGF and PES matrix. This is clearly evident from the FTIR (Fourier Transform Infrared Spectrometry) studies. The hydrodynamic interaction parameter (h) show negative values, suggest the improved interaction in SGFR‐PES composites by the generation of excess friction at the interface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43647.     

硫铝酸盐水泥作纤维增强砼的实验研究

预应力纤维增强水泥砼比起不加预应力的有着许优点。但是,由于基质的收缩,应力作用将减少。如果采用硫铝酸盐水泥,可以减少基质的收缩。文章介绍了二组关于硫铝酸盐水泥砼基本物理机械性能的实验,讨论了外加剂对砼性能的影响,并提出:外加剂的比例是制造纤维增强水泥板技术的重要参数。     

玻璃纤维增强PEEK复合材料成型工艺研究

本文初步探索了玻璃纤维增强聚醚醚酮(PEEK)复合材料的成型工艺．通过力学性能、微观形貌分析等试验,探索了不同工艺参数对玻璃纤维增强PEEK复合材料性能的影响,进而制定了复合材料较优的成型工艺参数．其成型工艺参数包括冷却速度、成型压力、成型温度、保温时间．     

MDC-29型电解槽钢衬玻璃钢槽盖的制作

从材料的选择、衬贴工艺、质量检查、防腐性能等方面详细介绍了用197#树脂制作MDC-29型电解槽钢衬玻璃钢槽盖的过程.其完全能够代替MDC-29型电解槽全玻璃钢槽盖.     

Development of glass fibre reinforced polyethylene pipes for pressure applications

Abstract

Thermoplastic filament winding with in line melt impregnation has been investigated for the manufacture of continuous glass fibre reinforced thermoplastic pipes. With polyethylene matrixes it was found that the high melt viscosity hindered full melt impregnation and resulted in high pull forces in the case of pipe grade polyethylene. Using a lower viscosity polyethylene it was possible to operate the melt impregnation process, but the product obtained exhibited a high void content. Surprisingly, it was found that filament winding resulted in a considerable decrease in void content, to an acceptable level. It was found possible to wind good quality pipes and achieve high failure pressures that fully reflected the strength of the reinforcement.

The non-linear strain response of glass–polyethylene pipes can be modelled using laminate theory modified to take account of the non-linearity of the matrix and the change in fibre angle that occurs as the pipe deforms.     

乙烯基玻璃钢在氯碱工业中的应用

介绍了乙烯玻璃钢的特点及其在氯碱工业中的应用。     

碳纤维增强水泥/混凝土材料力学性能的若干研究

本文通过对水泥基体掺入碳纤维进行研究，得出了复合体抗压强度、劈拉强度与碳纤维掺量的关系。同时文中还利用聚丙烯腈纤维作对比研究，得出目前碳纤维作为增强体的优缺点，为碳纤维增强水泥基复合材料的推广应用提供更多的实验依据。     

Silica or fibre glass reinforced composites via photopolymerisation of acrylate systems

Abstract

Composites based on an acrylate system were cured using UV light in the presence of a radical photoinitiator, with silica powder or glass fibres as reinforcing agents. The presence of small amounts of silica or glass fibres (up to 7 wt-%), did not influence the kinetics of photopolymerisation or the final conversion of the acrylic double bonds. The properties of the materials obtained were found to depend on the type and concentration of the reinforcing agent, and the surface treatment.