Improved process moldability and part quality of short-glass–fiber-reinforced polypropylene via overflow short-shot water-assisted injection molding
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Wei Zhang
,
Tang-qing Kuang
,
Jia-mei Lai
Abstract
Water-assisted injection molding (WAIM) is a promising molding process developed based on conventional injection molding (CIM). It has been a research hotspot in recent years and is still receiving extensive attention from many scholars and industries because of its significant potential advantages in practical applications. However, compared with CIM, since the additional water-related parameters are involved, the process moldability of thermoplastics is significantly reduced, especially for fiber-reinforced thermoplastics, which stunts the development of WAIM process. In this work, short-shot WAIM with an overflow cavity (OSSWAIM) was developed to address the problems and broaden the application scope of WAIMs. The results showed that compared with overflow WAIM (OWAIM) and short-shot WAIM (SSWAIM), OSSWAIM could significantly improve the process moldability and part quality of fiber-reinforced thermoplastics, especially for thermoplastic composites with a high fiber weight fraction. Besides, it was also found that water penetration had a slight influence on the fiber orientation near the water inlet, but had a significant influence on the fiber orientation near the end of mold cavity. Finally, three processing parameters affecting the water penetration, i.e., water pressure, melt temperature, and water injection delay time were investigated in terms of their influences on the fiber orientation within OSSWAIM.
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Author contributions: All the authors have accepted responsibility for this work and approved submission.
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Research funding: This work is financially supported by the National Natural Science Foundation of China (NSFC, Nos. 21664002, 51563010, 52163006), Natural Science Foundation of Jiangxi Province (No. 20181BAB206014), and Major Basic Research Projects of Jiangxi Province (No. 20203BBE53065), for which the authors are very grateful.
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Conflict of interest statement: The authors declare that they have no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
- Material Properties
- Approach to quantify the resistance of polymeric foams against thermal load under compression
- Characterisation of melamine formaldehyde microspheres synthesised with prolonged microencapsulated reaction time
- Changes in the morphology, mechanical strength and biocompatibility of polymer and metal/polymer fabricated hydroxyapatite for orthopaedic implants: a review
- Structure and mechanical properties of a multilayer biomedical shaft tubing: effect of layer composition
- Preparation and Assembly
- An environmentally sustainable isosorbide-based plasticizer for biodegradable poly(butylene succinate)
- MMA-based fast-curing repair materials suitable for low-temperature application
- Engineering and Processing
- Effect of combination printing parameter (infill density and raster angle) on the mechanical and electrical properties of 3D printed PLA/ZnO and cPLA/ZnO composites
- Improved process moldability and part quality of short-glass–fiber-reinforced polypropylene via overflow short-shot water-assisted injection molding
- Assessment of processibility and properties of raw post-consumer waste polyethylene in the rotational moulding process
