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1.
In this research, reinforcing effect of hybrid filler including rice husk (RH), beech bark (BB) and nano-SiO2, in polypropylene has been investigated. In the sample preparation, four levels of filler loading were used for waste lignocellulosic materials (55-58 wt.%) and nano-SiO2 (0-4 wt.%). In order to increase the interphase adhesion, polypropylene grafted with maleic anhydride was added as a coupling agent to all the composites studied. The physical properties, viz. the thickness swelling and water absorption, and mechanical properties, namely, the tensile, flexural and notched Izod impact strengths, of the composites were determined. Generally, high amount of filler content in composites can lead to the reduction of interfacial adhesion between matrix polymer and filler, and it limits their applications. The results showed that while flexural properties and elongation at break were moderately improved by the increase in the amount of filler in the matrix, tensile and Izod impact strengths decreased dramatically. However, the composites had acceptable mechanical strength levels. The mechanical properties of composites filled with RH are generally greater than BB composites. The thickness swelling and water absorption of the composites increased with the increase in the filler loading, but to a negligible extent as compared with the wood-based composites and the solid woods. Nano-SiO2 addition showed little positive effect on the mechanical properties. It can be concluded from this study that the used waste lignocellulosic materials are attractive reinforcements from the standpoint of their physico-mechanical properties.  相似文献   

2.
The mechanical properties of the nanocomposites are dependent, not only of the clays content but, also, of the resin type and manufacturing process. In this context, the present study intends to develop a systematic study involving a low glass transition temperature (Tg) and low permeability epoxy resin (SR 1500 and the hardener SD 2503) with a commercially Nanomer I30 E nanoclays. Two dispersion processes were compared (direct (DM) and indirect method (IDM)) in terms of mechanical properties, as well as the influence of nanoclay content and hydro aging effect. It was possible to observe that the composites obtained by the indirect method present lower mechanical properties than the neat resin because there is residual acetone. For DM composites the tensile strength, fracture toughness and the specific energy absorbed by impact decreases with the reinforcement content, caused by particle agglomerates. Elastic modulus, at 25 °C, increases significantly and Tg increases slightly with the addition of nanoclays. Hydro aging promotes a progressive decreasing of the tensile strength and fracture toughness, with the clay content, reaching about 15 % and 7 %, respectively, for 6 wt% of nanoclays. On the other hand, a small increasing on specific energy absorbed was observed.  相似文献   

3.
Rice husk is a by-product of rice milling process, and a great resource as a raw biomass material for manufacturing value-added composite products. One of the potential applications is to use rice husk as filler for manufacturing gypsum–rice husk boards for wall and ceiling materials for construction. We investigated the effect of rice husk, addition on selected physico-mechanical properties, total volatile organic compound (TVOC), and incombustibility, on the gypsum board. With increasing rice husk contents, water and moisture absorption was decreased. Because of the replacement of pore between gypsum particles by rice husk, the moisture absorption was decreased as rice husk adding contents. By rice husk adding, MOR of the gypsum–rice husk boards were increased up to 9.8 MPa at 30 wt%. However, MOR was decreased more than 40 wt% of adding contents. The modulus of elasticity (MOE) showed similar behavior with MOR. However, internal bonding strength (IB) was slightly increased as rice husk adding contents up to 20 wt%, 0.5 MPa and decreased over 20 wt%. The incombustibility of the gypsum–rice husk boards decreased on increasing the rice husk adding content. However, up to 30 wt% of rice husk adding contents board samples was of incombustibility first class. Gypsum particle can be replaced up to 30 wt% by rice husk with incombustibility first class for housing materials. In all cases, TVOC emission factor and formaldehyde emission remained under the ‘Excellent’ grade as defined by Korean Air Clean Association (KACA).  相似文献   

4.
Bio-based CaCO3 powder was synthesized via size reduction method from waste eggshells. The XRD analysis revealed that eggshell powder consists of CaCO3 in calcite form. The inclusion level of CaCO3 contents were varied of 5, 10, 15, 20 and 25 wt.% of prepared CaCO3-polyester film. Effects of different proportions of prepared chicken eggshell and commercial CaCO3 filler on the polyester resin composites films were compared by means of mechanical and physical test. It was found that the addition of CaCO3 filler to the polyester films leads to improve the mechanical properties. The findings revealed that the best and optimum CaCO3 filler content was 10 wt.% and among the prepared polyester films, eggshell CaCO3-polyester films showed the best performance. The mechanical properties of CaCO3-polyester films were measured in terms of tensile strength, elongation-at-break, tensile modulus, flexural strength and impact strength. For eggshell CaCO3- polyester films, the maximum values of the aforementioned mechanical properties were 52.70 MPa, 4.63 %, 1868.70 MPa, 101.20 MPa and 8.40 kJ/m2, respectively, whereas for commercial CaCO3-polyester films those values were 48.12 MPa, 4.50 %, 1790.30 MPa, 97.50 MPa and 8.21 kJ/m2, respectively. Further, water absorption of the composite films as a function of time had also been investigated at 10 wt.% filler content.  相似文献   

5.
This study aims to investigate the impact of rice-husk power generation on agricultural uses of rice husk and its ash. We conducted case studies at a rice-husk power plant and organic farming groups in northeast Thailand. The case study on a rice-husk power plant showed that rice husk was useful in generating electricity without consuming fossil fuel, while husk ash, the by-product, could be utilized as silicate supplement for farmland soils. The case study on organic farming groups indicated that rice husk was one of the indispensable materials in conducting organic farming with locally available resources. On the basis of these findings, an analytical study on possible husk uses in Thailand was conducted, in which three potential major uses of rice husk were considered: i.e. (1) fuel use inside rice mills followed by husk-ash reuse, (2) fuel use at power plants followed by husk-ash reuse, and (3) direct reuse of husk for compost production. The result indicated that there would be conflicting demands for rice husk among those uses in the future. Therefore, there needs to be a strategy for balancing husk uses among them.  相似文献   

6.
The clam shell (CS) waste was first modified by furfural and hydrochloric acid to prepare fillers FCS and ACS, which were then used as fillers in polypropylene (PP), as well as the commercial calcium carbonate (CC). These fillers were characterized and analyzed by means of X-ray diffraction (XRD), atomic force microscopy (AFM), particle size analyzer, Fourier transformed infrared spectroscopy (FTIR) and contact angle measurement. The mechanical and thermal properties of PP composites were investigated as well. XRD analysis indicated that the major crystalline phase of CC was calcite; of shell waste derived fillers, calcite and aragonite. The CC was fully hydrophobic, while the shell derived fillers were amphiphilic. Mechanical property studies showed that the incorporation of FCS played the role mainly of toughening the PP; of CC, CS and ACS, that of reinforcing. The optimum filler contents of CS, ACS and FCS could reach 5, 7 and 15 wt.%, respectively, to obtain a good balance between fracture toughness and stiffness of the PP composites. Polarized optical microscopy (POM) observation indicated that the inclusion of these fillers could promote the heterogeneous nucleation of PP.  相似文献   

7.
This study was conducted to evaluate the suitability of using residual plant fibers from agricultural waste streams as reinforcement in thermoplastic composites. Three groups of plant fibers evaluated included cotton burrs, sticks and linters from cotton gin waste (CGW), guayule whole plant, and guayule bagasse. The plant fibers were characterized for physical (bulk density and particle size distribution) and chemical properties (ash, lignin and cellulose contents). A laboratory experiment was designed with five fiber filler treatments, namely control (oak wood fiber as the filler - OWF), cotton burr and sticks (CBS), CBS with 2% (by weight) second cut linters (CBL), CBS with 30% (by weight) guayule whole plant (CGP), and CBS with 30% (by weight) guayule bagasse (CGB). The composite samples were manufactured with 50% of fiber filler, 40% of virgin high-density polyethylene (HDPE), and 10% other additives by weight. The samples were extruded to approximately 32 × 7 mm cross-sectional profiles, and tested for physico-mechanical properties. The CBS and CBL had considerably lower bulk density than the other fibers. Cotton linters had the highest α-cellulose (66.6%), and lowest hemicellulose (15.8%) and lignin (10.5%) of all fibers tested. Guayule whole plant had the lowest α-cellulose and highest ash content. Both CBS and guayule bagasse contained α-cellulose comparable to OWF, but slightly lower hemicellulose. Evaluation of composite samples made from the five fiber treatments indicated that fibers from cotton gin byproducts and guayule byproducts reduced the specific gravity of the composites significantly. However, the CBS and CBL samples exhibited high water absorption and thickness swelling, but the addition of guayule bagasse reduced both properties to similar levels as the wood fiber. The CGP exhibited significantly lower coefficient of thermal expansion. Composite samples with the five different fiber fillers showed similar hardness and nail holding capacity, yet oak fibers imparted superior strength and modulus under flexure and compression with the exception of the compressive modulus of CGB composites. In general, both cotton ginning and guayule processing byproducts hold great potential as fiber fillers in thermoplastic composites.  相似文献   

8.
The objective of this study is to characterize the fatigue strength of a Kevlar/epoxy laminate composite as well as the benefits obtained by using an epoxy matrix filled by cork powder. Twelve ply laminates, all in the same direction, of woven bi-directional Kevlar 292, were prepared by hand lay-up, using an SR 1500 epoxy resin. The composite sheets were produced by a vacuum moulding process. The addition of cork powder reduces the static strength, however, in terms of fatigue strength a similar behavior was found for both laminates.  相似文献   

9.
This paper presents the physicochemical and nutrimental characterization of fresh nopal (Opuntia ficus indica, Redonda variety) and nopal powder produced at different stages of development. Nopal powder was obtained by dry vacuum technique using 102 Torr and low temperature (40°C). The results showed that the nutrimental and mineral composition of nopal changes as a function of the maturation as follow: The ash content increases from 18.41 for nopalitos (60 g of weight) to 23.24% (nopal pads 200 g); calcium content increases from 1.52 to 3.72%, while phosphorous exhibits an opposite trend: 0.43 to 0.27%, respectively. Calcium oxalate was determined by X-ray diffraction and SEM microscopy and quantified by using atomic absorption spectroscopy. Calcium oxalate decreases from 7.95 to 3.47 mg/g and the Ca/P ratio varies from 3.6 to 11. The soluble fibre decreases from 25.22 to 14.91%, while insoluble fibre increases from 29.87 to 41.65%. These results suggest that nopal could be an important source of minerals within the diets of people in Mexico and the rest of Latin America.  相似文献   

10.
Rice husk charcoal (RC) produced from the pyrolysis of rice husk (RH) can be one of the cost-effective biochars for use in rice-based farming systems. This study investigated changes in rice yield and soil carbon sequestration over three years of RC application to an Andosol paddy field. The treatments were RC application at 0.02, 0.2, and 2 kg m?2 (RC0.02, RC0.2, and RC2, respectively), RH application at 0.2 kg m?2 (RH0.2), and a control with no RC or RH application (CONT). The results showed that RC2 increased culm length by 4% and straw weight by 14% on average over the three years. These increases in plant growth coincided with a higher level of silicon uptake by the rice plants, although they did not significantly affect grain yield. The soil carbon content was progressively increased by RC2 over the three years, whereas it was not significantly affected by RC0.02 or RC0.2. A considerable amount (>72%) of the applied carbon with RC2 remained in the soil by taking account of its downward movement below the 10 cm layer of the paddy field after three consecutive years of RC application. We conclude that rice husk charcoal application to Andosol paddy fields is an effective option for increasing carbon sequestration. Furthermore, the increase in silicon uptake by rice plants suggests that rice husk charcoal can also be functioning as a silicon fertilizer.  相似文献   

11.
不同轻型基质对金钱树生长影响初报   总被引：2，自引：1，他引：1  
采用单纯形-格子设计,将农林废弃物的椰糠、甘蔗渣、碳化稻壳、中药渣按体积比混合,得到35种轻型基质。结果表明,不同基质对金钱树的苗高、地径、根系生长、生物量有显著差异,经过综合评分,得出6种较好基质,分别为:100%椰糠;75%椰糠:25%碳化稻壳;50%甘蔗渣:50%中药渣;50%椰糠:50%中药渣;25%椰糠:50%碳化稻壳:25%中药渣;25%椰糠:25%甘蔗渣:25%碳化稻壳:25%中药渣。  相似文献   

12.
The graphene oxide (GO) sheets are chemically grafted with γ-etheroxygentrimethoxysilane (KH560) and liquid crystalline epoxy (LCE) is synthesized from 4,4′-bis(2-hydroxyhexoxy)biphenyl (BP2) and epichlorohydrin before being incorporated into epoxy matrix. Then we present a novel approach to the fabrication of advanced polymer composites from epoxy matrix by incorporation of two modifiers, which are grafted GO (g-GO) and LCE. The mechanical properties of epoxy composites are greatly improved by incorporating LCE/g-GO hybrid fillers. For instance, the addition of 3 wt% hybrid filler (2 wt% g-GO and 1 wt% LCE) into the epoxy matrix resulted in the increases in impact strength by 132.6 %, tensile strength by 27.6 % and flexural strength by 37.5 %. Moreover, LCE/g-GO hybrid fillers are effective to increase thermal decomposition temperature, glass transition temperature, and storage modulus by strong affinity between the fillers and epoxy matrix.  相似文献   

13.
Sodium adsorption ratio (SAR) is one of the water quality indexes that whose is important due to reuse or depletion to environment. Solutes in drain water can be controlled by adsorption, chemical or biological reaction, organic envelope of drainage. Rice husk is the common option of drainage envelops in paddy fields. In this study, the ability of reduction of SAR by rice husk was evaluated in batch scale and physical model of drain envelops. In the batch experiments, the adsorption of SAR parameters was investigated by adding 2 g of rice husk into a 100 ml of sodium chloride solution. The results indicated that rice husk absorbed calcium, magnesium and sodium, respectively. By increasing the temperature, contact time and pH, adsorption of calcium, magnesium and sodium was increased; however, the higher concentration of sodium in soil solution reduced the percentage of adsorption. In a more realistic state, physical models of subsurface drainage in the paddy fields were made. Drainage envelope treatments included of rice husk (H), combination of 20 and 60 % of husk with gravel (H20G80 and H60G40) and a pipe without envelope (NE). Due to higher drain discharge and more sodium removal (lower SAR in drain water), treatment H with the discharge of 16.2 ml/min and SAR of 1.27 (meq/l)0.5 was better in comparison with other treatments.  相似文献   

14.
Polyurethane (PU) films containing different amounts of fly ash particles (FAPs) were prepared by simple solution casting method. The morphological, thermal, and mechanical properties of the composite films were investigated by several characterization methods. Results show that sufficient amounts (up to 40 wt%) of FAPs can be incorporated throughout the film. The presence of FAPs within PU film not only acts as filler to increase the mechanical strength of the film but also increases its volatile organic compounds (VOCs) adsorption capacity. The VOCs adsorption capacity of FAPs/PU composite films were investigated on three different compounds (chloroform, toluene, and benzene). It showed consistent trend in the order of toluene > benzene > chloroform for all the samples. The VOCs adsorption capacity of PU film was found to be increased by two fold when 20 wt% of FA was incorporated through it. The present results suggest the potential use of FAPs as filler materials for PU films with improved VOCs adsorption from outdoor and indoor air.  相似文献   

15.
为提高软木地板表面的物理性能,采用弹性漆对软木地板表面进行涂饰处理,研究不同弹性漆的涂漆量、油漆固化温度对软木地板表面耐磨、耐冲击性、表面色度学特性的影响。结果表明：与对照相比,软木地板表面漆膜具有优良的耐磨性、表面磨耗值随着弹性漆涂漆量的增加而降低,表面磨耗值为0.015 6～0.031 0 g/100 r;弹性漆对软木地板表面抗冲击改善幅度较大;油漆固化温度和涂漆量对软木地板表面颜色影响较小。  相似文献   

16.
This paper presents the results of a current study on polypropylene matrix composites processed by injection, with two different glass fiber lengths and five different volume fractions. Physical and mechanical properties were obtained, namely flexural strength, stiffness modulus and fracture toughness. The mechanical properties of the composites increased significantly with the increase of the fibers volume fraction in agreement with the Counto model. The effect of water immersion time was also analysed. Immersion in water promotes a marked decrease in mechanical properties in the early seven-ten days, and afterwards tends to stabilize. Water causes a decrease of the relative strength which increases with fiber volume fraction and reaches about 29 % and 32 % for 20 % of 4.5 mm fiber length and for 25 % of 12 mm fiber length respectively, after 28 days immersion in water. Fracture toughness increases with fiber volume fraction and is always higher for 12 mm fiber length composites than for 4.5 mm fiber length composites.  相似文献   

17.
Cork in the outer bark of trees is among the valuable raw materials of biological origin due to properties that result mainly from its cellular structure. Large scale commercial utilization of cork has been only achieved with cork from Quercus suber. Another oak species, Quercus cerris, also contains substantial, albeit not continuous, regions of cork that are clearly visible to the naked eye but are so far considered as a waste material.Bark samples of Q. cerris var. cerris trees were collected from the And?r?n province, Turkey. Cork portions were separated and their cellular structure was investigated with optical and electron scanning microscopy observations. The results were compared with Q. suber cork.Q. cerris cork has the typical features of cork tissues with a regular and radially aligned structure of suberized cells without intercellular voids, showing a ring structure and a distinction of earlycork and latecork cells. Solid volume fraction was estimated at 25% (22% in earlycork, 36% in latecork).In Q. cerris cork cells are smaller, cell wall thickness and solid volume fraction are higher, and the tissue is less homogeneous with a higher content of lignified inclusions than in Q. suber cork. These factors will negatively influence quality in regard to density and mechanical properties associated to elasticity. However, this does not impair its use for production of granulates and agglomerates, e.g. for insulation and energy absorption. Separation of the cork fraction from the bark is a step required before further processing and use.  相似文献   

18.
This study has examined the flexural properties of natural and chemically modified coir fiber reinforced cementitious composites (CFRCC). Coir fibers of two different average lengths were used, and the longer coir fibers were also treated with a 1 % NaOH solution for comparison. The fibers were combined with cementitious materials and chemical agents (dispersant, defoamer or wetting agent) to form CFRCC. The flexural properties of the composites, including elastic stress, flexural strength, toughness and toughness index, were measured. The effects of fiber treatments, addition of chemical agents and accelerated ageing of composites on the composites’ flexural properties were examined. The results showed that the CFRCC samples were 5–12 % lighter than the conventional mortar, and that the addition of coir fibers improved the flexural strength of the CFRCC materials. Toughness and toughness index, which were associated with the work of fracture, were increased more than ten times. For the alkalized long coir fiber composites, a higher immediate and long-term toughness index was achieved. SEM microstructure images revealed improved physicochemical bonding in the treated CFRCC.  相似文献   

19.
李勇 《中国马铃薯》2014,(3):147-151
为了探讨马铃薯原原种适宜的生产基质问题,选用‘荷兰15号’和‘克新13号’的脱毒苗为试验材料,采用单因素随机设计,共设计14种基质类型,分析了不同基质类型对马铃薯原原种产量性状(商品薯产量和总产)和经济参数(利润和经济效益)的影响。研究结果表明:对于‘荷兰15号’品种而言,采用"草炭+炉灰=3:1"的基质,可获得最高的产量和效益;其次是"草炭+珍珠岩+炉灰=2:1:1"和"草炭+珍珠岩+稻壳=2:1:1",采用这些基质也可获得较好的产量和效益。对于‘克新13号’品种而言,采用"草炭+珍珠岩+炉灰=4:2:1"的基质,可获得最高的产量和效益;其次是"草炭+炉灰=3:1"的基质,采用这种基质也可获得较好的产量和经济效益。  相似文献   

20.
适宜机械粒收玉米品种脱水特性及相关性状研究   总被引：1，自引：0，他引：1  
以5个不同熟期玉米杂交种为试验材料,通过玉米子粒含水率、脱水速率及相关性状测定,比较不同玉米品种脱水等性状。试验结果表明,适合粒收品种华美1号与其他品种相比,具有生育期短、含水率低、生理成熟后脱水速率快和果皮薄等特点,2016年生理成熟和收获时含水率分别为32.25%和20.20%,2017年分别为35.28%和17.47%。相关分析结果表明,子粒脱水速率与果皮厚度呈极显著负相关,相关系数为-0.975;与苞叶脱水速率和含水率呈显著相关,相关系数分别为0.935和-0.950;与其他性状相关性不显著。  相似文献   

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