Effect of nanoclay on the mechanical and damping properties of aramid short fibre‐filled styrene butadiene rubber composites

The effect of nanoclay loading on the alteration of tensile and dynamic mechanical properties of aramid short fibre‐filled styrene butadiene rubber composites was investigated. In all the composites, 20 phr of N330 black was used. Dynamic mechanical thermal analysis was used to investigate the viscoelastic damping at lower dynamic strains. Compressive hysteresis was evaluated to characterize higher strain static damping properties. Matrix–fibre interaction and filler distribution were investigated using morphological analyses. Matrix–filler interface, estimated by the half height width of the tan δ peak, plays a major role in energy dissipation. The matrix–fibre interaction parameter shows a similar trend with low strain tensile stress values. Nanoclay addition to the composites leads to improved elongation at break and frequency damping properties. Compressive hysteresis reflects no improvement of hysteresis with nanoclay loading. Dynamic storage moduli, matrix–fibre interaction parameter and energy dissipation properties of the short fibre‐filled composites are negatively affected by nanoclay addition. However, ultimate elongation is improved markedly on nanoclay addition. In respect of tensile strength and elongation at break values, two composite samples (KF5NC10 and KF10NC10) offer optimum properties. Copyright © 2009 Society of Chemical Industry     

Uncured and cured state properties of fly ash filled unsaturated polyester composites

Physical properties of fly ash filled unsaturated polyester composites in both uncured and cured states have been studied with special reference to the effect of degree of loading, nature of filler surface, and surface treatment of filler. The effect of filler surface on curing and oil absorption characteristics of filler were also examined. In the uncured state, sedimentation rate test and viscosity measurement for fly ash reinforced composites were performed. For cured fly ash filled unsaturated polyester composites, tensile properties decreased with the addition of fly ash particles whereas surface treatment led to improved mechanical properties and resistance to swelling. In terms of dynamic mechanical thermal analysis, effects of both filler and surface treatment on loss factor (tan δ) were discussed. Tan δ value and damping temperature range increased to the 15% fly ash addition. The composite having 15% unsilanized fly ash was found to have the highest tan δ and damping temperature range together with maximum performance in terms of tensile properties and swelling behavior. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1128–1136, 2000     

Thermomechanical properties of alkali treated jute‐polyester/nanoclay biocomposites fabricated by VARTM process

A systematic study was carried out to investigate the effect of alkali treatment and nanoclay on thermomechanical properties of jute fabric reinforced polyester composites (JPC) fabricated by the vacuum‐assisted resin transfer molding (VARTM) process. Using mechanical mixing and sonication process, 1% and 2% by weight montmorillonite K10 nanoclay were dispersed into B‐440 premium polyester resin to fabricate jute fabric reinforced polyester nanocomposites. The average fiber volume was determined to be around 40% and void fraction was reduced due to the surface treatment as well as nanoclay infusion in these biocomposites. Dynamic mechanical analysis (DMA) revealed enhancement of dynamic elastic/plastic responses and glass transition temperature (T_g) in treated jute polyester composites (TJPC) and nanoclay infused TJPC compared with those of untreated jute polyester composites (UTJPC). Alkali treatment and nanoclay infusion also resulted in enhancement of mechanical properties of JPC. The maximum flexural, compression, and interlaminar shear strength (ILSS) properties were found in the 1 wt % nanoclay infused TJPC. Fourier transform‐infrared spectroscopy (FT‐IR) revealed strong interaction between the organoclay and polyester that resulted in enhanced thermomechanical properties in the composites. Lower water absorption was also observed due to surface treatment and nanoclay infusion in the TJPC. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Development of Silicon Carbide Reinforced Jute Epoxy Composites: Physical,Mechanical and Thermo-mechanical Characterizations

The aim of the present study was to investigate the physical and thermo-mechanical characterization of silicon carbide filled needle punch nonwoven jute fiber reinforced epoxy composites. The composite materials were prepared by mixing different weight percentages (0–15 wt.%) of silicon carbide in needle punch nonwoven jute fiber reinforced epoxy composites by hand-lay-up techniques. The physical and mechanical tests have been performed to find the void content, water absorption, hardness, tensile strength, impact strength, fracture toughness and thermo-mechanical properties of the silicon carbide filled jute epoxy composites. The results indicated that increase in silicon carbide filler from 0 to 15 wt.% in the jute epoxy composites increased the void content by 1.49 %, water absorption by 1.83 %, hardness by 39.47 %, tensile strength by 52.5 %, flexural strength by 48.5 %, and impact strength by 14.5 % but on the other hand, decreased the thermal conductivity by 11.62 %. The result also indicated that jute epoxy composites reinforced with 15 wt.% silicon carbide particulate filler presented the highest storage modulus and loss modulus as compared with the unfilled jute epoxy composite.     

Addition of unmodified nanoclay to improve the performance of unsaturated polyester resin coating on natural stone

In this study, an unsaturated polyester resin (UPR) thin coating containing styrene monomer has been used to consolidate Brown Emperor natural stone pieces. Different amounts (0.5-2 wt%) of nanoclay was added to reduce shrinkage during cure and to impart both stiffness and toughness. The uncured UPR-nanoclay hybrids were characterized by rotational rheology, the gelation was monitored by means of a texture analyzer and the viscoelastic and thermal properties were determined in the cured UPR-nanoclay films. Transmission electron microscopy (TEM) was used to establish the degree of dispersion of the nanoclay in the UPR-nanoclay composites. The mechanical performance of the UPR-nanoclay thin coated natural stone pieces was measured by means of 3-points bending and impact strength tests.Addition of nanoclay (0.5 and 1 wt%) increased noticeably the viscosity to the UPR resin. The gel time of the UPR resin was significantly decreased by adding small amounts of nanoclay due to the interactions between the filler and the styrene in the UPR resin. Moreover, addition of nanoclay decreased the shrinkage degree during curing of UPR resin. In the cured composites, improved thermal properties in UPR were reached by adding nanoclay due to the creation of a network between the filler and the polymer matrix. Bundle nanometric size nanoclay agglomerates were observed which did not affect the glass transition temperature but increased the viscoelasticity of the UPR-nanoclay composites. Furthermore, the improved properties of UPR by adding nanoclay produced enhanced impact strength to coated natural stone pieces, as both stiffness and toughness were improved by nanoclay addition. Finally, good adhesion of nanoclay filled UPR to the surface of natural stone was reached.     

Preparation of porous polyester composites via emulsion templating: Investigation of the morphological,mechanical, and thermal properties

Open porous polyester composites were prepared by the crosslinking of unsaturated polyester resin and divinylbenzene in water‐in‐oil concentrated emulsion templates with the presence of a conventional surface modified montmorillonite nanoclay. Medium and high internal phase emulsions with either 55 or 80 wt% of internal phase were used as templates. The effect of monomer composition, emulsifier concentration, and internal phase amount on the emulsion stability and the morphology of the resulting porous composites were investigated. Moreover, the morphological properties of the resulting composites were determined depending on the amount of nanoclay loading. It was found that the morphological features, namely surface area and cell diameter, were altered dramatically with the amount of nanoclay loading. An important part of the research was focused on the variation of mechanical and thermal properties with the incorporation of nanoclay particles. The mechanical properties were improved both with the nanoclay incorporation and the use of medium internal phase emulsions. However, the used nanoclay did not have a significant effect on the thermal stability of the resulting composites. POLYM. COMPOS., 37:1531–1538, 2016. © 2014 Society of Plastics Engineers     

Synthesis of flame retardant polyester‐urethanes and their applications in nanoclay composites and coatings

This paper describes the synthesis of phosphorus‐containing polyester‐urethanes and their applications in nanoclay composites and coatings. Polyester was prepared by the reaction of bis(bisphenol‐A) monophenyl phosphonate, maleic anhydride and phthalic anhydride. The polyester was reacted with various diols such as ethylene glycol, diethylene glycol and propylene glycol to obtain polyester polyols. Synthesized polyester polyols were characterized by chemical analysis and instrumental analysis and was used further to react with different isocyanates to develop polyester‐urethanes. The synthesized polyester‐urethanes were blended with organo‐modified montmorillonite nanoclay (1 wt%, 3 wt% and 5 wt%) and were cast in a mold and coated on mild steel panels. The thermal stability of neat polyester‐urethane and the nanoclay composites was determined by thermogravimetric analysis. The flame retardant properties of cast films and their composites were determined by the limiting oxygen index and UL‐94 test methods. The physical and mechanical properties of coatings such as pot life, drying properties, scratch hardness, pencil hardness, impact resistance, adhesion and flexibility were investigated. The chemical resistance properties of the coatings were also determined in different reagents. The data reveal that the polyester‐urethane nanoclay composites with 3 wt% clay hold promise for use in effective flame retardant coatings. © 2013 Society of Chemical Industry     

Effect of nanoclay on physical,mechanical, and microbial degradation of jute‐reinforced,soy milk‐based nano‐biocomposites

Jute‐reinforced, soy milk‐based nano‐biocomposites were fabricated using both natural and organically modified nanoclay to study their effect on physical, mechanical, and degradation properties. Different weight percentages of nanoclays were used to modify soy milk by solution casting process. The jute fibers were then impregnated in modified soy resin and compressed to fabricate nano‐biocomposites. About 5 wt% of organically modified nanoclay‐loaded jute composite showed maximum tensile and flexural strength. X‐ray diffraction and transmission electron microscopy (TEM) analysis of fabricated composites confirmed about the formation of nanostructure. Impact, microhardness, dynamic mechanical analysis results of nano‐biocomposites revealed that nanoclay has influenced to improve such physical and mechanical properties. Microbial degradation study of nano‐biocomposites was carried out in cultured fungal bed. Weight loss, tensile loss, and field emission scanning electron microscopy photographs of composites revealed that composites are biodegradable in nature. The prime advantages of these composite are their eco‐compatibility as jute and soy resin, the basic constituents of composites are biodegradable in nature. These composites can be utilized in automobile, packaging, furniture sectors by replacing nondegradable plastic‐based composite. POLYM. ENG. SCI., 54:345–354, 2014. © 2013 Society of Plastics Engineers     

The effect of alkalization and fiber loading on the mechanical properties of bamboo fiber composites,Part 1: — Polyester resin matrix

Bamboo strips [10 cm × 1.5 cm × (1?1.5) mm] were treated with caustic solutions for 1 h at different concentrations e.g., 0, 10, 15, 20, and 25%. Bamboo strips reinforced polyester resin composites were fabricated by hand‐lay‐up technique using both alkali‐treated and untreated bamboo strips, using a room temperature curing system for the polyester resin. This study aims at the evaluation of the influence of caustic concentration on the mechanical properties of bamboo strips reinforced polyester resin composites at a constant 50% loading of reinforcement. Maximum improvement in property was achieved possibly with 20% of caustic treated strip reinforcements. Beyond 20%, there was degradation in all the strength properties because of failure in mechanical properties of the reinforcements itself. The effect of fiber loading variation upon mechanical properties was also studied. It was observed that superior mechanical properties were obtained with 60% filler loading. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Bamboo fiber reinforced thermosetting resin composites: Effect of graft copolymerization of fiber with methacrylamide

Epoxy and polyester resins have been reinforced with methacrylamide (MAA) treated bamboo strip matting to develop bamboo fiber reinforced plastic composites. Bamboo mats were graft copolymerized with 1, 3, and 5% solution of MAA. The mechanical (tensile strength, elastic modulus, flexural strength, and flexural modulus), thermal, and water absorption properties of the composites were determined. One percent treatment of bamboo with MAA gave optimum results with epoxy resin. The mechanical properties were improved. TGA results reveal that the degradation temperature of the composite has improved after grafting. The weight loss of 1% MAA treated bamboo–epoxy composite reached a value of 95.132% at 795°C compared to 97.655% at 685°C of untreated bamboo–epoxy composite. Water absorption in the composites was studied by long term immersion and 2 h boiling in distilled water. The process of water absorption indicates Fickian mode of diffusion. MAA treatment results in reduced water uptake. There was improvement in the properties of pretreated bamboo‐polyester matrix composite as well. Three percent treatment of bamboo with MAA gave optimum results with polyester resin. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effects of nanoclay and coupling agent on the physico‐mechanical,morphological, and thermal properties of wood flour/polypropylene composites

This article presents the effects of coupling agent and nanoclay (NC) on some properties of wood flour/polypropylene composites. The composites with different NC and maleic anhydride grafted polypropylene (MAPP) contents were fabricated by melt compounding in a twin‐screw extruder and then by injection molding. The mass ratio of the wood flour to polymer was 40/60 (w/w). Results showed that applying MAPP on the surface of the wood flour can promote filler polymer interaction, which, in turn, would improve mechanical properties of the composite as well as its water uptake and thermal stability. Composite voids and the lumens of the fibers were filled with NC, which prevented the penetration of water by the capillary action into the deeper parts of composite. Therefore, the water absorption in composites fabricated using NC was significantly reduced. Scanning electron microscopy has shown that the treatment of composites with 5 wt% MAPP, promotes better fiber–matrix interaction, resulting in a few numbers of pull‐out traces. In all cases, the degradation temperatures shifted to higher values after using MAPP. The largest improvement on the thermal stability of composites was achieved when NC was added. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers     

Impact of delignification on mechanical,morphological, and thermal properties of wood sawdust reinforced unsaturated polyester composites

Mechanical, morphological, and thermal properties of the raw and delignified wood sawdust (DWS) reinforced unsaturated polyester (UP) composites were evaluated. Composites were prepared using Resin Transfer molding technique by changing filler loading (5, 10, 15, and 20 wt%) for both raw and DWS reinforced UP. Mechanical (tensile and flexural), Fourier transform infrared spectroscopy (FTIR), morphological (scanning electron microscopy [SEM]) and thermal (thermogravimetric analysis [TGA]) properties were successively characterized. FTIR confirmed the removal of lignin from wood sawdust during the delignification process. The tensile strength, Young's modulus, and flexural strength values increased only up to 15% filler loading then decreased with increasing the filler. DWS reinforced composites had better mechanical properties compared to raw composites. SEM micrographs reveal that DWS reinforced composites have good compatibility with UP resin. According to TGA results, DWS reinforced composites showed enhanced thermal stability at the final decomposition stage above 400°C. J. VINYL ADDIT. TECHNOL., 24:185–191, 2018. © 2016 Society of Plastics Engineers     

Utilization of Flyash as Filler Material in Hybrid Polyester Composites for Improved Thermo-Mechanical and Erosion Wear Behavior

The present work was carried out for the utilization of major quantities of flyash as filler material in the short fiber reinforced polyester resin composites in various engineering and structural applications. The incorporation of flyash modifies the hardness, tensile, flexural, impact and damping behavior of the composites. It is observed that hardness, flexural modulus and impact strength of flyash filled composites increases with increase in the flyash filler contents. Whereas, with the addition of flyash contents it is observed that there is decrease in tensile strength and flexural strength. But beyond the 10 wt.-% flyash filler addition in the composite the flexural strength increases. At the end, the erosion wear behavior of all the composites has been studied by Taguchi experimental design. It is found that unfilled glass polyester composite suffers greater erosion loss as compare to particulate filled glass polyester composites. The eroded surface morphology is examined by SEM and the related erosion wear mechanism is discussed in detail.     

Thermal properties and processability of talc‐ and calcium carbonate‐filled poly(vinyl chloride) hybrid composites

The main objective of this investigation was to study and compare the thermal rigidity, thermal stability, and processability of poly(vinyl chloride) (PVC) composites filled with single fillers of talc and uncoated ground CaCO₃ (SM 90) or a hybrid filler consisting of talc/SM 90. To produce the composites, the PVC resin, fillers, and other additives were dry‐blended in a laboratory mixer before being milled into sheets by using a two‐roll mill. Test specimens were prepared by compression molding, after which the thermal properties and processability of the composites were determined. Single and hybrid filler loadings used were fixed at 30 phr (parts per hundred parts of resin). Talc‐filled PVC composite showed slightly better thermal stability and rigidity than the composite filled with SM 90, and its thermal stability and rigidity slightly decreased with SM 90 content increasing from 5 to 25 phr in order to replace talc filler in the hybrid composites. The fusion time of talc‐filled PVC composite was shorter than that of SM 90‐filled PVC composite; thus, the fusion time of hybrid composites increased with increasing SM 90. The fusion torque showed an opposite behavior. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers     

Investigation on Physico-Mechanical Properties,Water, Thermal and Chemical Ageing of Unsaturated Polyester/Turmeric Spent Composites

Nutraceutical industrial residues are potential fillers to fabricate green or eco-friendly polymeric composite materials as they are, less costly and easily available. Attempts have been made to use turmeric spent (TS)—a nutraceutical industry waste with a high E-factor to improve need-based properties of plastics. A series of unsaturated polyester resin composites have been fabricated with different turmeric spent content viz., 5, 10, 15 and 20% w/w. The effect of amount of filler content on tensile strength, physical properties including density and surface hardness and chemical resistance of the composites were determined. The influence of water and thermal ageing on the tensile strength of turmeric filler loaded unsaturated polyester composites has been studied.     

Effects of nanoclay on the properties of cardanol‐modified‐resol‐epoxy‐novolac composite material

A nanocomposite based on nanoclay and resol that was modified with cardanol, a natural alkyl phenol, shows improvement for the glass‐fiber‐reinforced epoxy‐composite system. Dispersion of the nanocomposite was investigated by X‐ray, showing good results obtained by the in situ polymerization method. The mechanical properties of the final composites were improved by doping a 6 wt% of nanoclay in cardanol‐modified‐resol (CMR) into the epoxy matrix. The results show that a 15 wt% of CMR in epoxy is a most suitable ratio. Using polyamide as a curing agent instead of other traditional systems, such as anhydrides or amines for epoxy resin, overcame important limitations, further allowing for improved processability. The overall composite performance was enhanced. Additionally, the thermal stability of the system was investigated by thermal gravimetric analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3238–3242, 2007     

Fabrication and characterization of novel zirconia filled glass fiber reinforced polyester hybrid composites

Novel hybrid glass fiber reinforced polyester composites (GFRPCs) filled with 1‐5 wt % microsized zirconia (ZrO₂) particles, were fabricated by hand lay‐up process followed by compression molding and evaluated their physical, mechanical and thermal behaviors. The consumption of styrene in cured GFRPCs was confirmed by Fourier transform infrared spectroscopy. The potential implementation of ZrO₂ particles lessened the void contents marginally and substantially enhanced the mechanical and thermal properties in the resultant hybrid composites. The GFRPCs filled with 4 wt % ZrO₂ illustrated noteworthy improvement in tensile strength (66.672 MPa) and flexural strength (67.890 MPa) while with 5 wt % ZrO₂ showed 63.93% rise in hardness, respectively, as compared to unfilled GFRPCs. Physical nature of polyester matrix for composites and an improved glass transition temperature (T_g) from 103 to 112 °C was perceived by differential scanning calorimetry thermograms. Thermogravimetric analysis revealed that the thermal stability of GFRPCs was remarkably augmented with the addition of ZrO₂. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43615.     

Effect of processing routes on the mechanical, thermal and morphological properties of PLA-based hybrid biocomposite

Due to environmental awareness and depletion of petroleum oil, bioplastics and their composites are one of the most researchable topics throughout the world. Polymers that are produced from renewable sources are expected to be the best alternative to replace conventional polymers. The bottles neck of these bioplastics is its cost which limits its application in certain purposes. Bioplastics filled or reinforced with natural fibers can reduce cost and improve properties, like stiffness, strength and toughness of biocomposites. Impact strength and fracture toughness are the main demerits of short fiber-filled biocomposite. On the other hand, when nanoclay, having a very high aspect ratio, is mixed with bioplastics it may significantly affect the thermal and mechanical properties of the final composites. A composite may also suffer dispersion inefficiency, which is considered the key factor to improve the properties. The aim of this paper was to hybridize nanoclay and short kenaf fiber in polylactic acid (PLA) by double extrusion method and followed by mechanical, thermal and morphological characterizations. Mechanical properties showed improvement with nanoclay, specifically the impact strength increased more than 50 % compared with unreinforced PLA. A double extruded composite showed 3–10 % better tensile and flexural properties than the single extruded composite. Similarly, addition of nanoclay increased decomposition and melting temperatures (T _m) from 198 to 225 °C and 152 to 155 °C, respectively. Crystallization temperature (T _c), however, dropped with nanoclay from 116 to 106 °C and storage modulus (E’) increased by about 1 GPa. These findings were also supported by scanning electron micrograph (SEM) and transmission electron micrograph (TEM) where in double extruded composite a better dispersion of nanoclay was observed. By employing X-ray diffraction (XRD) it was found that higher percentage of crystallinity was obtained while Fourier transform infrared (FTIR) displayed new bond formation. The presence of nanoclay enhanced thermal and mechanical properties of the hybrid composite.     

Comparison of the Mechanical and Thermo-Mechanical Properties of Unfilled and SiC Filled Short Glass Polyester Composites

This paper presents a comparison between particulate filled (SiC particles) and unfilled glass polyester composites on the basis of their mechanical and thermo-mechanical properties. The results show that particulate filled composites have a decreasing trend in mechanical properties when compared to the unfilled glass polyester composites. In particulate filled composites, the tensile and flexural strength of the composites decrease with the addition of 10 wt.-% SiC particles but increase with 20 wt.-% SiC particles. In the case of the unfilled glass polyester composite, the tensile and flexural strength of the composites increase with an increase in the fiber loading. However, higher values of tensile strength and flexural strength of particulate filled glass polyester were found than that of the unfilled glass polyester composite. In the case of thermo-mechanical and thermal properties, the particulate filled composites show better dynamical and thermal properties when compared to the unfilled glass polyester composites. The mechanical and thermal properties (i.e. thermal conductivity) are also calculated using FE modeling (ANSYS software) and the results from this simulation shows good agreement with the experimental results.