jute-PP Composites Research Articles

Heat insulating jute-reinforced recycled polyethylene and polypropylene bio-composites for energy conservation in buildings

The development of jute-reinforced recycled polyethylene (PE) and polypropylene (PP) bio-composites using a heat-pressed molding technique and the feasibility of using them as thermal-insulating panels in building interiors have been studied in the current research. Lignocellulosic natural jute fibers of different volume fractions were employed as reinforcement to fabricate recycled PP and PE composites, and their thermal and mechanical characteristics were investigated for the intended applications. The developed jute-PP composites showed a higher tensile (75.16 MPa) and flexural (121.13 MPa) strength compared to jute-PE with the tensile and flexural strength of 55.62 MPa and 74.53 MPa, respectively, which is attributed to the better tensile strength of PP and its superior interfacial bonding with the jute fiber than PE. The fractographic investigation also confirmed the desired interfacial attachment of reinforcement and recycled polymers in the composite structure. The heat barrier characteristics, including low thermal conductivity (0.2694 W/m.K and 0.1852 W/m.K for jute-PE and jute-PP, respectively) and enhanced conductive and radiative heat resistance with increased volume fraction of jute fiber, specified adequate heat barrier performance of the developed composites for building thermal applications. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) study revealed comparable thermal stability of both composites at elevated temperatures. Additionally, due to reduced interfacial vacuity and the existence of hydrophobic PE and PP, composite samples demonstrated very low water absorption with time, which suggested the potentiality of utilizing them as durable heat-insulating materials in building structures. Accordingly, the fabrication of thermal-insulating engineered recycled biocomposites and their application in designing green buildings can significantly contribute to reducing the global carbon footprint associated with thermal energy consumption of buildings and alleviating the growing environmental problems of plastic waste by utilizing them as matrix polymer in fiber-reinforced composites.

Flame resistance and heat barrier performance of sustainable plain-woven jute composite panels for thermal insulation in buildings

Global environmental awareness and stringent regulations laid the foundation for utilizing natural fibers alternative to synthetic fibers in polymeric composites due to their biodegradability and low carbon footprint. This research demonstrates the fabrication of natural jute-reinforced polypropylene biocomposite and investigates its utilization for heat insulation in buildings. Different volume fractions of cellulosic jute fiber as reinforcement were used to fabricate jute-polypropylene (jute-PP) composites, and mechanical and thermal performance was assessed by comparing them with the commercial gypsum board. The developed composites exhibited considerably higher tensile and flexural strength than the commercial specimen because of strong interfacial adhesion between jute fiber and polypropylene. Such stable bonding at the interface of reinforcement and matrix was also confirmed by the fractographic investigation. The thermal characteristics, including the low thermal conductivity and enhanced conductive and radiative heat resistance, revealed the superior thermal barrier performance of jute–PP composites compared to their commercial counterpart. The developed composites also demonstrated almost comparable flame resistance due to the presence of lignin in jute fiber. The thermogravimetric analysis revealed the inferior thermal stability of jute–PP composites at high temperatures. Besides, the low water absorption because of reduced interfacial vacuity indicated the potentiality of using jute–PP composites in the structure with durability. Hence, designing green buildings utilizing such heat-insulating engineered biocomposites is expected to alleviate the burgeoning global carbon dioxide emission associated with the energy consumption of buildings and promote the sustainable growth of this industry.

Tensile strength and thermal behavior of jute fibre reinforced polypropylene laminate composite

In the current era, sustainability and biodegradability are two necessary terms, which are related to the composite materials. Due to environmental sustainability use of the natural fibres as reinforcement is increased in composites for various applications as compared to glass fibre. In this research work, jute fibres are used as reinforcement due to the low cost and Polypropylene (PP) as matrix due to its ease of availability. The novelty of the work is to study the effect of plying of PP sheets on the tensile strength and thermal behavior of PP-Jute laminate composites by using simple hot press machine. Effect of polymer degradation due to repeated thermal processing on the mechanical performance of composite is also investigated. In this work the effect of the fibre cut length (3 cm, 6 cm and 9 cm), number of plies (1, 2 and 4) and fibre loading (0%, 5% and 10%) is studied. The structural, thermal and mechanical properties of the composites are investigated using X-Ray diffraction, tensile test, DSC and dynamic mechanical analysis. It is observed that the mechanical properties of composite improved up to 2 plies and deteriorate thereafter. Best results are obtained for 2-plied composites at all levels of fibre loading. Crystallinity percentage is reduced while crystallite size is increased in case of composites as compared to neat PP sheet. Jute-PP composites could be used for various applications in automobile industries, building components such as partitioning panels and similar applications.

Irradiated Jute Reinforced Polypropylene Composites: Effect of Mercerization and SEM Analysis

Jute fibres (Corchorus olitorious L.), an environmentally and ecologically friendly product, were chemically modified and treated as surface treatment which was carried out by mercerizing jute fabrics with aqueous solutions of NaOH (5,10 and 20%) at different soaking times (30, 60 and 90 minutes) and temperatures (0, 25 and 50°C). These mercerized jute fabric reinforced polypropylene composites were fabricated by composition molding technique and equated with virgin jute fabric reinforced polypropylene composites, fabricated by same technique. The above composite samples ware compared by evaluating the mechanical parameters such as tensile strength, tensile modulus, bending strength, bending modulus. The effect of mercerization on weight and dimension of jute fabrics was studied. Mechanical properties of mercerized jute-PP composites ware measured and found highest at 20% NaOH at 0°C for 60 min soaking time. Alkali treatment helped in the development of hydrophobicity and reduction in volume fraction of the porosity. This may be due to the better fibre matrix interface adhesion caused due to the fibre surface treatment by alkali. The optimized formulation was irradiated by γ radiation at different dosage (100, 150, 200, 250 & 500 Krad). Among them 250 Krad showed highest mechanical properties

Effect of mercerization on mechanical, thermal and degradation characteristics of jute fabric-reinforced polypropylene composites

Jute fabric reinforced polypropylene composites were fabricated by compression molding technique. Fiber content in the composites was optimized at 45 % by weight of fiber by evaluating the mechanical parameters such as tensile strength, tensile modulus, bending strength, bending modulus. Surface treatment of jute fabrics was carried out by mercerizing jute fabrics with aqueous solutions of NaOH (5, 10 and 20 %) at different soaking times (30, 60 and 90 mins) and temperatures (0, 30 and 70 °C). The effect of mercerization on weight and dimension of jute fabrics was studied. Mechanical properties of mercerized jute-PP composites were measured and found highest at 20 % NaOH at 0 °C for 60 min soaking time. Thermal analytical data from thermogravimetric and differential thermal analysis showed that mercerized jute-PP composite achieved higher thermal stability compared to PP, jute fabrics and control composite. Degradation characteristics of the composites were studied in soil, water and simulated weathering conditions. Water uptake of the composites was also investigated.

Jute fiber reinforced polypropylene composite: effect of chemical treatment by benzenediazonium salt in neutral medium

Jute fiber was treated with o-, m-, and p-hydroxybenzenediazonium salts in neutral media. These modified and raw jute fibers were used to prepare jute-polypropylene (PP) composite containing 20, 25, 30, and 35% by weight fraction. Mechanical properties of composites were studied. It was found that the increase in fiber content reduces the mechanical properties of jute-PP composite. However, treated jute fiber imparts better mechanical properties to jute-PP composite than the raw jute fiber. o-Hydroxybenzenediazonium salt (o-HBDS) treated jute-PP composites are found to be the best composite from the point of view of mechanical properties.

Lightweight Polypropylene Composites Reinforced by Long Switchgrass Stems

Switchgrass (SG) stems with lengths up to 10 cm have been used as reinforcement to make lightweight composites with polypropylene (PP) webs. The long SG stems, with simple cut or split and without chemical treatment, were used directly in the composites. Utilizing SG stems for composites not only increases the values of SG but also provides a green, sustainable and biodegradable material for the composites industry. Lightweight composites are preferred, especially for automotive applications due to the potential saving in energy. In this research, the effects of manufacturing parameters on the properties of composites have been studied. Although the tensile properties of SG stem are significantly worse than jute fiber, SG stem with low bulk density is found to better reinforce the lightweight composites. Compared with the jute-PP composites of the same density (0.47 g/cm3), composites reinforced by the split SG stems have 56% higher flexural strength, 19% higher modulus of elasticity, 15% higher impact resistance, 63% higher Young’s modulus, 52% lower tensile strength, and similar sound absorption property. The SG-PP composites with optimized properties have the potential to be used for industrial applications such as the support layers in automotive interiors, office panels and ceiling tiles.

A novel approach of manufacturing light-weight composites with polypropylene web and mechanically split cornhusk

A novel method has been developed to fabricate composites from mechanically split cornhusks (MSHs). This cost effective method will potentially open the door for a wide variety of agro-wastes in composites. The effect of holding temperature, MSH concentration, weight/area of web in between MSH layers, and MSH length on mechanical properties of composites has been investigated. The effect of MSH concentration on sound absorption has also been studied. Although the mechanical properties of MSH-PP are inferior to jute-PP composites, the former have 100% better sound absorption due to the presence of microair pockets in husks. At a substantially lower cost compared with other natural fibers, cornhusk presents an opportunity to reduce environmental pollution and to provide a higher profit margin to the farmers.

Effect of NaOH Treatments on Jute and Coir Fiber PP Composites

Changes occurring in jute and coir fiber composites with 2–8% concentration of a NaOH treatment for 24 h were investigated, respectively, for void content, microscopy images, mechanical properties and water absorption. The jute and coir fibers were vacuum dried before molding composite specimens. Mechanical properties indicated good adhesion between natural fibers and PP. Jute fibers, when alkali-treated with 2% concentration for 24 h, showed best improvement in tensile strength by 40% and modulus by 9%, respectively, while coir fibers, when alkali-treated with 6% concentration for 24 h, showed best improvement in tensile strengths by 62% and modulus by 17%, respectively. With 2% concentration of alkali-treatments, the elongation of jute and coir composites reached 8% and 13.5%, respectively. Moisture absorption for jute and coir composites are 50% and 60% lower than untreated fiber composites, respectively.

Studies on the Physicomechanical Properties of Sodium Periodate Oxidized Jute Reinforced Polypropylene (PP) Composites

In the present work, effects of oxidation and fiber content (from 20 to 35 wt. %) on the physicomechanical properties of jute-polypropylene (PP) composites were studied. Mechanical properties (tensile strength, tensile modulus, elongation at break, flexural strength, flexural modulus, and charpy impact strength) were measured for all raw and oxidized jute-PP composites. Improved mechanical properties were obtained for oxidized jute-PP composites. Interfacial adhesion and bonding between the fiber and PP matrix were investigated by scanning electron micrograph analysis. Improved interfacial interactions and reduced water absorption were found for oxidized jute-PP composites. Water absorption tests of all composites were also performed.

Abaca fibre reinforced PP composites and comparison with jute and flax fibre PP composites

Abaca fibre reinforced PP composites were fabricated with different fibre loadings (20, 30, 40, 50 wt% and in some cases 35 and 45 wt%). Flax and jute fibre reinforced PP composites were also fabricated with 30 wt% fibre loading. The mechanical properties, odour emission and structure properties were investigated for those composites. Tensile, flex- ural and Charpy impact strengths were found to increase for fibre loadings up to 40 wt% and then decreased. Falling weight impact tests were also carried out and the same tendency was observed. Owing to the addition of coupling agent (maleated polypropylene -MAH-PP), the tensile, flexural and falling weight impact properties were found to increase in between 30 to 80% for different fibre loadings. When comparing jute and flax fibre composites with abaca fibre composites, jute fibre composites provided best tensile properties but abaca fibre polypropylene composites were shown to provide best notch Charpy and falling weight impact properties. Odours released by flax fibre composites were smaller than jute and abaca fibre composites.

Effect of coupling agent on abrasive wear behaviour of chopped jute fibre-reinforced polypropylene composites

In this paper, studies have been conducted to investigate the abrasive wear behaviour of jute fibre-reinforced polypropylene composites. Effect of addition of maleic anhydride-grafted polypropylene (MA-g-PP)-coupling agent by two different approach, sliding distance and load on abrasive wear performance of jute fibre–PP composites has been determined by using a SUGA abrasion tester. Use of coupling agent gives better wear resistance as compared to without the use of coupling agent. It has also been found that addition of MA-g-PP coupling agent during melt mixing gives better wear resistance as compared to the jute PP composites having MA-g-PP solution-treated jute fibres, which has been explained on the basis of highest thermal stability of jute–PP Composite having melt-mixed MA-g-PP. Abrasive wear performance of the composites has been explained with the help of surface microstructures of worn surfaces.

Effect of MAPP as a Coupling Agent on the Performance of Jute–PP Composites

Like other natural fibers jute, because of its hydrophilic nature, is incompatible with nonpolar plastics matrices. This has been the major handicap for preparing stable composites. In this paper we have used maleic anhydride grafted polypropylene, MAPP(G-3015) as the coupling agent for the surface modification of the fibers. Various parameters such as effect of fiber length, MAPP concentration, time period of MAPP treatment, percentage (wt./wt.) of fiber loading on mechanical properties such as tensile, flexural and impact strengths have been studied. It has been found that 30% fiber loading with 0.5% MAPP concentration in toluene and 5 min impregnation time with 6 mm average fiber lengths give the best results. Nearly 72.3% increase in flexural strength was observed in respect of treated composites. The fiber matrix interface was analyzed from the SEM micrographs. Water absorption of the composites has also been considerably reduced in the treated composites. Thermal behavior of the composites were also studied through DSC measurements. The MFI study also supports better fiber matrix adhesion.