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Long fiber thermoplastic pellets are pellets containing discontinuous reinforced fibers and a matrix, offering excellent mechanical properties, good processability, recyclability, and low cost. Typically, commercial LFTP is manufactured through the hot melt impregnation process, combining extrusion and pultrusion. Although there is a thermoplastic pultrusion process for LFTP production, characterized by a simple machine and an easy method, its mechanical properties have not yet approached those of commercial LFTP. In improving the mechanical characteristics of LFTP manufactured via thermoplastic pultrusion, this research employed polypropylene-graft-maleic anhydride as a coupling agent during the injection molding procedure. The LFTP is composed of polypropylene material reinforced with glass fiber. Mechanical and physical properties of the LFTP were investigated by introducing PP-g-MAH at concentrations of 4, 8, and 12 wt% through injection molding. The results revealed that, at a 4 wt% concentration of PP-g-MAH, the LFTP composites exhibited heightened tensile, flexural and impact strengths. However, these properties began to decrease upon exceeding 4 wt% PP-g-MAH. The enhanced interfacial adhesion among glass fibers, induced by PP-g-MAH, contributed to this improvement. Nonetheless, excessive amounts of PP-g-MAH led to a reduction in molecular weight, subsequently diminishing the impact strength, tensile modulus, and flexural modulus. In LFTP composites, both tensile and flexural strengths exhibited a positive correlation with the PP-g-MAH concentration, attributed to improved interfacial adhesion between glass fibers and polypropylene, coupled with a reduction in fiber pull-out. Based on morphological analysis by SEM, the incorporation of PP-g-MAH improved interfacial bonding and decreased fiber pull-out. The presence of maleic anhydride in the LFTPc was confirmed through the utilization of FTIR spectroscopy. Mechanical properties of LFTP containing 4 wt% PP-g-MAH were found to be equivalent to or superior to those of commercial LFTP, according to the results of a comparative analysis. [ABSTRACT FROM AUTHOR]

Thermoplastic pultrusion is a suitable process for fabricating continuous unidirectional thermoplastics with a uniform cross-section, high mechanical properties due to continuous fiber reinforcement, low cost, and suitability for mass production. In this paper, jute and glass fibers were reinforced with a polypropylene matrix and fabricated using the thermoplastic pultrusion process. The volumetric fraction of the composite was designed by controlling the filling ratio of the reinforcing fiber and matrix. The effects of molding parameters were investigated, such as pulling speed and molding temperature, on the mechanical properties and microstructure of the final rectangular profile composite. The pulling speed and molding temperature varied from 40 to 140 mm/min and 190 to 220 °C, respectively. The results showed that an increase in molding temperature initially led to an increase in mechanical properties, up to a certain point. Beyond that point, they started to decrease. The resin can be easily impregnated into the fiber due to the low viscosity of thermoplastic at high temperatures, resulting in increased mechanical properties. However, the increase in molding temperature also led to a rise in void content due to moisture in jute fiber, resulting in decreased mechanical properties at 210 °C. Meanwhile, un-impregnation decreased with the increase in molding temperature, and the jute fiber began to degrade at high temperatures. In the next step, with varying pulling speed, the mechanical properties decreased as the pulling speed increased, with a corresponding increase in void content and un-impregnation. This effect occurred because the resin had a shorter time to impregnate the fiber at a higher pulling speed. The decrease in mechanical properties was influenced by the increase in void content and un-impregnation, as the jute fiber degraded at higher temperatures. [ABSTRACT FROM AUTHOR]

A long fiber thermoplastic pellet (LFTP) is a pellet that contains discontinuous fibers reinforced in thermoplastic. In this experiment, LFTPs were produced using the thermoplastic pultrusion process. The thermoplastic pultrusion process is uncomplicated in terms of the machine device, and it can improve the impregnation quality of LFTP. Glass fiber was used as the reinforced fiber, and PP fiber was used as the matrix. This experiment studied the effect of molding temperature and pulling speed on impregnation. The die system contained six heating zones. In the first step, zones 3 and 4 (melting zone) were varied at 200, 210, 220, and 230°C. The melting zone that exhibited good results was selected for the next step. In the second step, zones 5 and 6 (heat reduction zone) were varied at 160°C–190°C and 150°C–180°C, respectively. After determining the optimal molding temperature, the pulling speed was studied, with speeds varied at 10, 20, 30, 40, and 50 cm/min. The impregnated quality of the LFTP was investigated through microstructure analysis. A data logger was used to record the temperature profile in the pultrusion die. Furthermore, the impregnation quality and microstructure of LFTP from thermoplastic pultrusion were compared to commercial LFTP. The results showed that un-impregnation decreased with an increase in the melting zone temperature. In the heat reduction zone, un-impregnation decreased with a decrease in temperature. For the pulling speed, un-impregnation decreased with a decrease in speed. The optimal die system had a melting zone temperature of 230°C and a heat reduction zone temperature of 160 and 150°C. The optimal pulling speed was 10 cm/min, resulting in an un-impregnation rate of 8.06%. Additionally, commercial LFTP had an un-impregnation rate of 13.73%. Graphical Abstract [ABSTRACT FROM AUTHOR]

Abstract: The unidirection composites of jute spun yarn/Polylactic acid were fabricated using compression molding. The reinforcement fibers were paralleled with matrix resin fiber and were used as intermediate materials to prepare the unidrection preforms. The parallel yarn was winded onto the metallic frame. The wound paralleled yarns were dried in convection oven before molding. The metallic frame containing the paralleled yarns was placed in heated mold for consolidation to produce the unidirection composite specimens with various molding temperature. The heated mold was cooled by the cooling system of the compression machine. Consolidation process involved three stages. At first, under certain temperature, the solid fibrous matrix materials became softened and then the matrix in the liquid form soaked and infiltrated the reinforcing fibers and finally during cooling stage, the matrix turned into solid form to hold the fibers in a definite position. The molding temperature was affected to the mechanical properties of the unidirection composite. The jute spun yarn/PLA composite were characterized in the term of mechanical properties and the fabrication quality was examined by cross-section observation. The impregnation quality and dispersion of fiber bundle were increased with increasing the molding temperature and achievement ratio of elastic modulus increase. While increasing the molding temperature, the achievement ratio of tensile strength was decreased because of deterioration of jute fiber. The optimum compression molding temperature was 185 - 195C for fabricated the jute spun yarn/PLA unidirection composite. [Copyright &y& Elsevier]

Abstract: Pultrusion is a continuous process with application in the manufacture of fiber-reinforced composite. The thermoplastic pultrusion molding is a manufacturing process in which generated by the resin fiber and reinforcement fibers are pulled through the heat die. The pressure was generated, also the resin fiber start melt and impregnate into the reinforcement fiber. In this investigation study the mechanical properties of jute spun yarn/PLA tubular braided composite by pultrusion molding. The systems for jute spun yarn/PLA braided composite were described in the term of materials design, structure design and processing design. The intermediate materials were prepared by comingle technique. The braiding technique manufactured preform which had jute fiber diagonally oriented at certain angles with the glass fiber inserted into the braiding yarns along the longitudinal direction of braiding structure. The braided preforms were pulled through the heated die where consolidation flow took place due to reduced matrix viscosity. The pultrusion experiments were fabricated the tubular braided composite with varying the structure of braided preform and pultrusion molding condition. The configuration of intermediate material and the molding temperature are influenced to the mechanical properties of jute spun yarn/PLA tubular braided composite. The quality of pultruded composite was evaluated by cross-section observation and mechanical properties evaluated by 4-point bending test. [Copyright &y& Elsevier]

Abstract: Currently, the light has shed on the ecological-friendly products. The mulberry products, especially hand-made paper, are wildly facilitated as general wares or decoration. The research on the lamination of the mulberry paper with biodegradable films can ameliorate the usability, corresponding to the modernisation and green products. Meticulously, the laminating machine is designed and created in this research, with the size 98 x 118 x 126 centimetres. The machine is consisted of the roller driver and the infrared heater. The laminate film will be pulled by the roller driver and be passed the latex glue and infrared heater. Subsequently, the film will be coated on the mulberry paper by the rubber roller. The experimental results show that the best lamination is at speed 3.72 m/min. In addition, the biodegradable film has thickness 40μm and tensile strength is 40.22MPa. Tensile strength of normal mulberry paper is 37.07MPa, but 79.14MPa after the lamination. The laminated mulberry-paper is more attractive, strengthening, and lotus effect. The surface becomes smooth, easily to print and to clean out the dirt. [Copyright &y& Elsevier]

Thermoplastic pultrusion is a suitable process for fabricating continuous unidirectional thermoplastics with a uniform cross-section, high mechanical properties due to continuous fiber reinforcement, low cost, and suitability for mass production. In this paper, jute and glass fibers were reinforced with a polypropylene matrix and fabricated using the thermoplastic pultrusion process. The volumetric fraction of the composite was designed by controlling the filling ratio of the reinforcing fiber and matrix. The effects of molding parameters were investigated, such as pulling speed and molding temperature, on the mechanical properties and microstructure of the final rectangular profile composite. The pulling speed and molding temperature varied from 40 to 140 mm/min and 190 to 220 °C, respectively. The results showed that an increase in molding temperature initially led to an increase in mechanical properties, up to a certain point. Beyond that point, they started to decrease. The resin can be easily impregnated into the fiber due to the low viscosity of thermoplastic at high temperatures, resulting in increased mechanical properties. However, the increase in molding temperature also led to a rise in void content due to moisture in jute fiber, resulting in decreased mechanical properties at 210 °C. Meanwhile, un-impregnation decreased with the increase in molding temperature, and the jute fiber began to degrade at high temperatures. In the next step, with varying pulling speed, the mechanical properties decreased as the pulling speed increased, with a corresponding increase in void content and un-impregnation. This effect occurred because the resin had a shorter time to impregnate the fiber at a higher pulling speed. The decrease in mechanical properties was influenced by the increase in void content and un-impregnation, as the jute fiber degraded at higher temperatures.