Polypropylene and Linear Low-Density Polyethylene Two-Layered in Single-Step Rotational Molding at the High-Speed Rotating

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Ektinai Jansri
Jidapa Kromsuriyasak
Jakkphat Preedawat
Narongchai O-Charoen


The objective of this research has studied the molding of two-layered products in one-step rotational molding process at high-speed rotation. In this research, polypropylene (PP) with different sizes and shapes of particles were used to mixed with linear low-density polyethylene (LLDPE) with powder particles, using the single-axis rotation machine for molding, mixing by dry blend method at 50:50 ratios, the rotational speed at 60 rpm, during molding the temperature change within the mold and the particles movement behavior was observed and recorded. The results show clearly that high-speed rotation can cause the sample to be separated as two-layered in all cases, the surface roughness both inside and outside has reduced, and the sample had higher an initial modulus when compared to low-speed rotation except in the case of PP with round shape and 3 times larger than LLDPE

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Jansri, E., Kromsuriyasak, J., Preedawat, J., & O-Charoen, N. (2020). Polypropylene and Linear Low-Density Polyethylene Two-Layered in Single-Step Rotational Molding at the High-Speed Rotating. Journal of Engineering, RMUTT, 18(1), 153–164. Retrieved from https://ph01.tci-thaijo.org/index.php/jermutt/article/view/241895
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