MIT-World Peace University (MIT-WPU) is a top educational institute located in Pune, India. It is recognized within&nbsp;UGC under Government of Maharashtra Act No. XXXV 2017.&nbsp;

It is part of the MIT group of institutions (established in 1983) which covers 10+ campuses across India and has more than 50,000+ students enrolled across various disciplines at a given point of time. The institute houses 15 schools ranging from Engineering &amp; Technology, Design, Pharmacy, Commerce, Governance among others. It offers undergraduate, postgraduate and PhD programs among different disciplines.&nbsp;

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MIT World Peace University

Synthetic fibers were used as reinforcements for a long period of time due to their excellent properties and compatibility with natural rubbers. Tensile properties and manufacturability of natural fabrics- Jute and Bamboo are studied. Layer by layer type of composite was manufactured by compression moulding and the crosslinking of matrix and reinforcement was done by using chemlok 250 as adhesive. Properties obtained from the tests are given in this paper. Production was carried out in two stages, 1st stage was by using adhesive and the results were compared and based on these results 2nd stage of manufacturing was carried out without using adhesive and specimens of ASTM D412 standard die type A was obtained by water jet cutting. Tensile test was carried out on the basis of ASTM D412 standard. Results show that the strength of bamboo fabric as reinforcement increases the strength of material and can be used in many applications. Short fibers are always used as reinforcement in polymers for increasing their mechanical properties; one can also use the fabrics as reinforcement in different fields to increase the mechanical properties of the composites. © 2022 Elsevier Ltd. All rights reserved.

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School of Polymer Engineering

Materials Today: Proceedings

Uniaxial tensile properties for bamboo and jute fabric reinforced natural rubber

Wood plastic composites (WPC) were made from polypropylene (PP), impact copolymer (ICP) and wood flour (WF) by varying the WF content from 10 to 40% with PP grafted maleic anhydride as a coupling agent. The effect of varying WF content was studied on rheological, thermal, mechanical properties and dynamic mechanical properties. Experimental small amplitude oscillatory shear (SAOS) data was compared with the Einstein-Batchelor and empirical Krieger-Dougherty relations. Significant dependence of mechanical and rheological properties on WF content was observed. Young's modulus, flexural modulus and dynamic shear viscosity increased with WF content. Results of dynamic mechanical analysis (DMA) showed increase in storage modulus with WF content. Three millimeter thick compression molded composites sheets were thermoformed using axisymmetric molds with two draw depths. Sag observed visually during thermoforming decreased with increasing WF content. Components made from the composites showed close to uniform thickness distribution as compared to those from ICP. © 2021 Walter de Gruyter GmbH, Berlin/Boston.

Journal of Polymer Engineering

Study of effect of wood-flour content on mechanical, thermal, rheological properties and thermoformability of wood-polypropylene composites

The mechanical properties like tensile, pin bearing and impact properties have been studied for composites containing Fly Ash (FA) and Impact modifier (IM) in Polyvinyl Chloride (PVC) for furniture and pipe applications. Pin-bearing test is an important tool to evaluate the ability of the material to retain fasteners and the ability of the material to sustain load during the service life. The present paper evaluates the effect of variation of FA and IM on the pin bearing strength, tensile strength, modulus elongation at break and impact strength. Scanning electron microtopography indicates that the impact modifier forms a co-continuous phase at 10% of IM in PVC. Increase in void content decreases impact strength and tensile strength. As void content increases moisture absorption also increases. The results of pin bearing tests were analogous to tensile test and correlate well. Results were in accordance with impact modification theory. Moisture absorption was studied keeping in view outdoor applications.

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Journal of Minerals and Materials Characterization and Engineering

Experimental Investigation of Mechanical Properties of Impact Modified Polyvinyl Chloride-Fly Ash Composites

Concrete is one of the popular construction material used all over the world. But, over the last few decades,polymer concrete is being introduced in order to fulfil various constructional requirements (such as zero water absorption,quick setting time, earthquake resistance, impact barriers, high flexural strength, chemical resistance, etc.) The objective ofthis project is to improve the properties of concrete by incorporating polymer system so as to make it suitable forapplications like industrial flooring, thin section precast walls, etc. The project aims at evaluating compressive strength andwater absorption of polymer based concrete system over conventional concrete with and without fibrous reinforcements. Thesystem consisted of Polyurethane (water based emulsified resin), hardener, white cement, fine silica and fibrousreinforcement (polyester fibres).Overall, six formulations with varying fibre content were used for the studies. The standardsamples based on conventional concrete as well as polyurethane based concrete system were casted and subsequently testedfor compressive strength and water absorption after 28 days’ post casting. In both the cases, it has been observed that thecompressive strength did not increase drastically with varying content of polyester. The polyurethane based concrete systemhas very low set (curing) time as compared to conventional concrete. The compressive strength achieved by polyurethanebase concrete within 3 days was around 80% of its total strength (28 days) while conventional concrete achieved strengtharound 60% of its total strength within 7days of time. In case of conventional concrete there is necessity of water for itscuring while polyurethane based concrete water present as dispersion medium itself serves the required purpose. It was alsoobserved that polymer system based concrete has compressive strength comparable with M35 mix design of conventionalconcrete. Hence, using polyurethane based concrete material for ordinary and standard conventional concrete applicationscan be beneficial.

International Journal of Advances in Mechanical and Civil Engineering

Concrete based on polyurethane system

Polypropylene (PP) is one of the fastest growing thermoplastic polymers in the world, second only to polyethylene. This is primarily due to its excellent balance of physical and chemical properties at a lower cost. PP however possesses low melt strength on account of its linear structure and hence is not easily amenable to processing techniques that involve free surface stretching deformations like thermoforming, blow molding and extrusion film casting. One way to enhance the melt strength of PP is to incorporate long chain branches in its molecular architecture. The present study focuses on the impact of rheology of linear and branched PP on their thermoforming characteristics. Two grades each of linear and long chain branched (LCB) PP homopolymer and impact copolymer (ICP) were used. It was observed that the LCB-PP homopolymer and LCB-ICP showed higher flow activation energy, reduced value of loss tangent and nearly equal frequency dependence of storage and loss moduli in shear rheology. Also, a strong strain hardening behavior was displayed in extensional rheology by the LCB grades. Plug assist thermoforming experiments were carried out to assess the effect of long chain branching on surface strain and thickness distribution for axisymmetric cups of two draw ratios. Biaxial surface strain maps of the formed cups were quantified using Grid Strain Analysis (GSA). Thermoformed cups made from LCB-PP homopolymer and LCB-impact copolymer showed lower surface strain and overall higher thickness as compared to cups made from their linear counterparts, which is in accordance with what might be expected from their rheology.

International Polymer Processing

Study of Rheology and Plug Assist Thermoforming of Linear and Branched PP Homopolymer and Impact Copolymer

This paper explores the application of the cooling techniques and Moldex3D software for simulation of cooling system in the injection molding process. The effect of cooling systems as the most important factors in optimization of plastic injection molding. Optimization of cooling system plays a significant role in the quality, efficiency, and the cost effective manufacturing. The importance of shape, type, and the location of cooling channels using the Moldex3D software and good results are achieved. Using numerical simulation tools or combination of analytical and numerical simulation approach is one of the intelligent choices applied to modern mold cooling design. Keywords - Injection Molding, Moldex3D Software, Optimization of Cooling Channels.

International Journal of Mechanical and Production Engineering

Optimization of cooling system using simulation software in injection molding

Plug temperature is a key parameter affecting the thickness distribution of thermoplastic components made by plug assist thermoforming. For a specified pair of plug and plastic sheet, the variation in plug temperature can alter the coefficient of friction (COF) between the pair. We show here how the temperature dependence of COF influences the nature and extent of biaxial stretching of the sheet and consequently the thickness distribution of the thermoformed component. In the present study, high impact polystyrene (HIPS) sheets were thermoformed into axisymmetric cups using a plug-assist process in which the aluminum plug temperature (Tplug) was varied from ambient to above the glass transition temperature of HIPS (∼100 °C). Biaxial strain maps on the surfaces of the formed cups were measured and quantified using Grid Strain Analysis (GSA). Thickness distributions of the cups were also measured. Temperature dependent COF between HIPS and aluminum was determined independently using a rotational rheometer. The measured COF was low for T < 100 °C, whereas it increased appreciably at and above 100 °C. We conclude that when Tplug < 100 °C the HIPS sheet slips on the plug during forming, and this results in biaxial stretching of the base and walls of the formed cup. In contrast for Tplug > 100 °C, a significant reduction in the magnitude of slip is expected. Here the sheet is gripped at the clamp and by the plug during forming which causes reduced biaxial stretching of the base and increased uniaxial stretching of the walls of the cup. Simulations of plug-assist thermoforming using a temperature dependent COF showed qualitative agreement with the GSA data thereby supporting our inferences.

Effect of Plug temperature on strain and thickness distribution of components made by Plug Assist Thermoforming

The present article evaluates the effect of variation of WF on the tensile strength, modulus, and elongation at break. The pin-bearing properties usually correlate well with tensile properties. Tensile strength and pin-bearing strength decrease but tensile modulus increases on addition of WF. The tensile strength, pin-bearing strength, and mode of pin-bearing failure also depends on the void content. Increase in void content has a detrimental effect on all the mechanical properties. Wide variation is observed in impact strength because of unpredictable void content due to use of non-vented extrusion process. TGA indicates insignificant effect of WF on thermal stability of composites. Infrared spectroscopy indicates some interaction between PVC and WF. © The Author(s), 2010.

Journal of Reinforced Plastics and Composites

Mechanical properties of highly filled PVC/wood-flour composites

Viscoelastic and dielectric properties of composites with polyvinyl chloride as major matrix constituent, ethylene vinyl acetate (EVA) as polymeric plasticizer, and wood flour (WF) and fly ash (FA) as filler have been studied. The effect of variation of WF, FA, and EVA on storage modulus E', loss modulus E", and glass transition temperature, Tg has been evaluated using dynamic mechanical analysis (DMA). Effect on permittivity ε' and conductivity is evaluated using dielectric analysis. The results show considerable influence of constituents of the composite on the properties evaluated. DMA shows that WF contributes to an increase in Tg, E', and E" and a decrease in loss tangent, tan δ. The FA content has insignificant effect on these properties. Increasing WF content increases ε'. © 2009 Society of Plastics Engineers.

Polymer Engineering and Science

Characterization of highly filled wood flour-polyvinyl chloride composites: Dynamic mechanical and dielectric analysis

Composites with polyvinyl chloride (PVC) as major matrix constituent, ethylene vinyl acetate (EVA) as polymeric plasticizer and wood flour (WF) and fly ash (FA) as filler were extruded. Morphology of the samples was studied using scanning electron microscopy (SEM). Morphological study indicated good dispersion of the constituents. Infrared spectroscopy (IR) indicates interaction between EVA and PVC and also between the polymeric matrix and WF. The effect of various constituents on glass transition temperature (Tg) was evaluated using differential scanning calorimetry. Addition of EVA decreased the Tg, whereas Tg was increased due to addition of WF and FA. Study indicated that reduction in Tg on addition of EVA was compensated by increase in Tg due to addition of WF. The contribution of FA to change in Tg was not significant. Resulting composites have Tg close to that of PVC. © 2009 Wiley Periodicals, Inc.