The effect of pressure variations on the formation of gas inclusions in the rotational molding process
-
Martin Löhner
and
Dietmar Drummer
Abstract
The major disadvantage of rotational molding is the cycle time, which is very long compared to other plastic processing methods. A major percentage of the cycle time besides heating and cooling results from the time necessary to remove gas inclusions from the polymer melt, which are trapped while sintering the polymer powder. In this work the formation of gas inclusions is investigated by conducting a cycle time variation on a uniaxial rotational molding machine. The influence of low pressure during melting on the formation of inclusions is investigated by examining sintering experiments with a pressure variation during the melting of the polymer. Sintering experiments are conducted with different melt residence times to investigate the mechanisms of gas inclusion removal. By comparing the time to reach a pore-free polymeric melt, the cycle time reduction potential under low-pressure application while melting the polymeric powder is estimated.
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Articles in the same Issue
- Frontmatter
- Original articles
- Physico-mechanical characterization and biodegradability behavior of polypropylene/poly(L-lactide) polymer blends
- Tensile properties of polyformaldehyde blends and nanocomposites
- Interaction simulation and experimental physico-mechanical analysis of distinct polarity blends of polyethylene and polyvinyl alcohol
- Thermal degradation of high-density polyethylene/soya spent powder blends
- Combination of montmorillonite and a Schiff-base polyphosphate ester to improve the flame retardancy of ethylene-vinyl acetate copolymer
- Effects of initial crystallization process on piezoelectricity of PVDF-HFP films
- Characteristics of natural leather finished with some ecofriendly mixtures of polymeric aqueous dispersions
- Dye wastewater treatment by direct contact membrane distillation using polyvinylidene fluoride hollow fiber membranes
- The effect of pressure variations on the formation of gas inclusions in the rotational molding process
- Numerical study of filling strategies in vacuum assisted resin transfer molding process
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Articles in the same Issue
- Frontmatter
- Original articles
- Physico-mechanical characterization and biodegradability behavior of polypropylene/poly(L-lactide) polymer blends
- Tensile properties of polyformaldehyde blends and nanocomposites
- Interaction simulation and experimental physico-mechanical analysis of distinct polarity blends of polyethylene and polyvinyl alcohol
- Thermal degradation of high-density polyethylene/soya spent powder blends
- Combination of montmorillonite and a Schiff-base polyphosphate ester to improve the flame retardancy of ethylene-vinyl acetate copolymer
- Effects of initial crystallization process on piezoelectricity of PVDF-HFP films
- Characteristics of natural leather finished with some ecofriendly mixtures of polymeric aqueous dispersions
- Dye wastewater treatment by direct contact membrane distillation using polyvinylidene fluoride hollow fiber membranes
- The effect of pressure variations on the formation of gas inclusions in the rotational molding process
- Numerical study of filling strategies in vacuum assisted resin transfer molding process
- Effect of gas counter pressure on the carbon fiber orientation and the associated electrical conductivities in injection molded polymer composites
