On the Injection Molding of Long Glass Fiber Filled Thermoplastic Test Specimens

Abstract VERTON RF-700-12 is a 60% long glass fiber reinforced Nylon 6/6 injection molding compound. It has been engineered to maximize the benefits of long fiber reinforcement while maintaining the ease of processing and good fiber dispersion associated with conventional short fiber reinforced compounds. This datasheet provides information on tensile properties as well as fracture toughness. It also includes information on casting. Filing Code: Cp-3. Producer or source: ICI Advanced Materials.

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Effects of high-efficiency infrared heating on fiber compatibility and weldline tensile properties of injection-molded long-glass-fiber-reinforced polyamide-66 composites

Journal of Polymer Engineering ◽

10.1515/polyeng-2019-0211 ◽

2020 ◽

Vol 40 (2) ◽

pp. 173-180 ◽

Cited By ~ 1

Author(s):

Po-Wei Huang ◽

Hsin-Shu Peng

Keyword(s):

Tensile Strength ◽

Injection Molding ◽

Glass Fiber ◽

Tensile Properties ◽

Fiber Composite ◽

Mold Surface ◽

Polyamide 66 ◽

Glass Fiber Composites ◽

Glass Fiber Composite ◽

Long Glass Fiber

AbstractGlass fiber composites are prevalent molded materials used in various fields, including aviation engineering, automobile manufacturing, and medical equipment production. The length of a glass fiber affects the mechanical properties of a glass fiber composite. Studies have reported that breakage occurs in long fibers subjected to screw plasticization, injection processes, and geometrical changes in injection molding. Moreover, multigate injection molding can result in weldlines on the final product, consequently reducing its strength. Further exploration is required to determine how product strength is affected by weldlines generated through injection molding with glass fiber composites and how product tensile properties associated with weldlines can be improved. Therefore, this study designed a mold with a vent area and a plug-in mold-surface-heating device to examine changes in the weldlines and tensile properties of long-glass-fiber composite specimens fabricated through injection molding using two melts. The results revealed that fiber length decreased with increasing screw speed; such declines in fiber length affected the tensile strength of the long-glass-fiber-reinforced polyamide-66 composites. In addition, because the arrangement and distribution of the glass fibers were affected by the melt flow rate, melt flow direction, and changes in mold cavity volume, the weldline tensile strength varied with the depth of the vent area. Mold surface heating improved the specimen surface roughness by 5.79% and effectively improved the interfacial adhesion between the fibers and melts, thereby resulting in more favorable weldline tensile strength. This also notably reduced the depth of weldlines produced by the adhesion of two melts.

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The Low Breaking Fiber Mechanism and Its Effect on the Behavior of the Melt Flow of Injection Molded Ultra-Long Glass Fiber Reinforced Polypropylene Composites

Polymers ◽

10.3390/polym13152492 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2492

Author(s):

Po-Wei Huang ◽

Hsin-Shu Peng ◽

Sheng-Jye Hwang ◽

Chao-Tsai Huang

Keyword(s):

Injection Molding ◽

Glass Fiber ◽

Fiber Length ◽

Mold Cavity ◽

Fiber Breakage ◽

Melt Flow ◽

Molding Machine ◽

Glass Fiber Reinforced ◽

Long Glass Fiber ◽

Long Fibers

In this study, fiber breaking behavior, fiber orientation, length variation, and changes in melt flow ability of long glass fiber reinforced polypropylene (L-FRP) composites under different mold cavity geometry, melt fill path, and plasticization parameters were investigated. The matrix material used was polypropylene and the reinforcement fibers were 25 mm long. An ultra-long-fiber composite injection molding machine (with a three-stage plunger and injection mechanism design) was used with different mold cavity geometry and plasticization parameters. Different screw speeds were used to explore the changes in fiber length and to provide a reference for setting fiber length and parameter combinations. Flow-length specimen molds with different specimen thickness, melt fill path, and gate design were used to observe the effect of plasticizing properties on the flow ability of the L-FRP composite materials. The experimental results showed that the use of an injection molding machine with a mechanism that reduced the amount of fiber breakage was advantageous. It was also found that an increase in screw speed increased fiber breakage, and 25 mm long fibers were shortened by an average of 50% (to 10 mm). Long fibers were more resistant to melt filling than short fibers. In addition, the thickness of the specimen and the gate design were also found to affect the filling process. The rounded angle gate and thick wall product decreased the flow resistance and assisted the flow ability and fiber distribution of the L-FRP injection molding.

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Influence of low-fracture-fiber mechanism on fiber/melt-flow behavior and tensile properties of ultra-long-glass-fiber-reinforced polypropylene composites injection molding

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0120 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Po-Wei Huang ◽

Hsin-Shu Peng ◽

Sheng-Jye Hwang ◽

Chao-Tsai Huang

Keyword(s):

Injection Molding ◽

Glass Fiber ◽

Fiber Length ◽

Glass Fibers ◽

Melt Flow ◽

Molding Machine ◽

Injection Molding Machine ◽

Glass Fiber Reinforced ◽

Flow Length ◽

Long Glass Fiber

AbstractIn this study, an injection molding machine with a low-fracture-fiber mechanism was designed with three stages: a plasticizing stage, an injection stage, and a packing stage. The fiber-fracture behavior is observed under the screw (plasticizing stage) of low-compression/shear ratio for the ultra-long fiber during the molding process. The molding material employed in this study was 25-mm-ultra-long-glass-fiber-reinforced polypropylene (PP/U-LGF). In addition, a thickness of 3 mm and a width of 12 mm spiral-flow-mold were constructed for studying the melt flow length and flow-length ratio through an experiment. The experimental results showed that the use of an injection molding machine with a three-stage mechanism decreased the fiber length when the screw speed was increased. On average, each fiber was shortened by 50% (>15 mm on average) from its original length of 25 mm. Longer glass fibers were more resistant to melt filling, and as the fiber length was reduced, the mixing between the melt and glass fibers was improved. Thus, the melt fluidity and fiber ratios were increased. In addition, the mixing/flow direction of the melt had an impact on the dispersion and arrangement of glass fibers, thus the tensile strength of PP/U-LGF increased.

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