• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.159-162
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• 1999

The purpose of this research was to study the effects of initial moisture levels and extrusion temperatures on dietary fiber, nitrogen solubility index, available lysine, and the in vitro protein digestibility of extruded oat productes. The dehulled grains were ground in a Brabender quadrumat Senior mill and the coarse fraction, with higher crude protein, lipids and dietary fiber were conditioned on various mositre levels (15.5~25.5%) and extruded in a Brabender single-screw laboratory extruder. The extrudates showed a higher amount of soluble dietary fiber (8.14%) than in the raw material . However, the extrusion process affected the nutritional value of the protein due to a decrease in available lysine with increased temperature . The in vitro protein digestibility was unaffected by initial moisture levels and the extrusion temperatures examined.

• Elastomers and Composites
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• v.56 no.4
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• pp.217-222
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• 2021

In this study, random polypropylene (rPP) was compounded with two of monoglycerides, namely, glyceryl monolaurate (GML) and glyceryl monostearate (GMS), as antifogging agents to improve its antifogging performance. rPP film samples were prepared by a film-casting method using a three-roll casting machine after melt blending through a twin screw extruder. With an increase in the monoglyceride content, the melt flow index for rPP films with GML and GMS increased, and their yield strength decreased. The incorporation of GMS in rPP was proven to be more effective in improving its physical properties than was rPP with GML. When GML and GMS were separately added to the rPP film at contents of more than 1 phr and more than 5 phr, respectively, the film exhibited antifogging performance.

• Steel and Composite Structures
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• v.38 no.2
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• pp.177-187
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• 2021

The effect of nanoparticle volume fraction on the elastic properties of a polymer-based nanocomposite was experimentally investigated and the obtained results were compared with various existing theoretical models. The nanocomposite was consisted of high density polyethylene (HDPE) as polymeric matrix and 0, 0.5, 1 and 1.5 wt.% multi walled carbon nanotubes (MWCNTs) prepared using twin screw extruder and injection molding technique. Nanocomposite samples were molded in injection apparatus according to ASTM-D638 standard. Therefore, in addition to morphological investigations of the samples, tensile tests at ambient temperature were performed on each sample and stress-strain plots, elastic moduli, Poisson's ratios, and strain energies of volume units were extracted from primary strain test results. Tensile test results demonstrated that 1 wt.% nanoparticles presented the best reinforcement behavior in HDPE-MWCNT nanocomposites. Due to the agglomeration of nanoparticles at above 1 wt.%, Young's modulus, yielding stress, fracture stress, and fracture energy were decreased and Poisson's ratio and failure strain were increased.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.456-460
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• 1990

The processing conditions for the production of meat snack were investigated by using a Bonnot Single-screw extruder Pork and thicken meat were mixed with corn flour in various ratios, respectively, and extruded at different screw speeds(120-260 rpm). As the meat content was increased, the expansion ratio, water absortion index, lightness and yellowness of the extrudate were decreased. The expansion ratio tended to increase with an increase in screw speed, but the opposite relationship was observed with the maximum meat content(meat corn flour=2:1). The maximum water absorption ratio was obtained at the screw speed of 190rpm when the meat content was relatively low, but it moved to 120 rpm as the meat content was increased. The bulk density of the extrudate was significantly increased as the meat content exceeded 50% and no significant differences in bulk density was found at the highter meat content. The redness increased as the moisture content was increased. The maximum breaking strength was attained at the meat-corn flour ratio 1 : 1, and the breaking strength tended to decreased as the screw speed increased.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.666-673
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• 1988

The enhancement of the growth of lactic bateria in rice-based beverage was achieved by the prefermentation of cereals with a mixed culture of Bacillus and yeast followed by extrusion cooking. The rice-soybean milk blend was inoculated with a mixed culture of Bacillus laevolactis and Saccaromyces cerevisiae, and fermented in solid state at $45^{\circ}C$. It was extruded in an autogenous single screw extruder for sterilization as well as for partial digestion, and subjected to lactic fermentation in liquid state. The combined prefermentation and extrusion cooking increased the content of water soluble solid. It stimulated the growth of lactic bacteria as well as the acid production and increased dispersion stability and sensory acceptability.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.578-583
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• 2000

To use onion pomace produced from concentrated onion juice processing, dried onion pomace or dried onions were mixed with com grits at levels of 10, 20, and 30% and were extruded in a twin-screw extruder. Quality properties of extruded onion snack were investigated. Low-lignin dietary fiber of dried onion pomace was approximately 2 times higher than that of dried onion. Browning increased with increasing onion content. Reducing sugar and free sugar in onion snack showed high content by increasing onion concentration and the majority of free sugar consisted of glucose and fructose. Flavonoid in control snack was not detected and the flavonoid content containing quercetin and quercetin glycosides was about 50% less in onion pomace snack than in onion snack. Sensory evaluation of onion snack containing 10% concentration of dried onion pomace or dried onion indicated the products were acceptable in overall eating-quality.

• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.157-162
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• 2021

In this study, 3D printing filaments using recycled polypropylene (rPP) were produced by a single screw extruder. Graphene composite filament was also prepared using electrochemically exfoliated graphene (EEG) as a composite filler by adding 10, and 20 wt% of EEG to rPP. The graphene and rPP were successfully dispersed with great homogeneity, so that 3D filaments were uniformly produced, and their thermal properties increased as the graphene content increased. The mechanical property was also improved when EEG was 10 wt% but decreased when EEG was 20 wt% compared to that of rPP. 3D structures were successfully manufactured using prepared 3D filaments by a conventional 3D printer, and great advantages can be expected in terms of environmental and economical perspective by adopting plastic waste.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.23-28
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• 2015

Lacquer sap extracted from lacquer trees exhibits good thermal stabilities and antimicrobial properties. To apply these superior properties to functional packaging, polyurushiol (YPUOH) powders were prepared and blended into LDPE (low density polyethylene) to prepare three different LDPE/YPUOH composite films via a twin screw extruder system. Their morphology, thermal and antimicrobial properties as well as barrier properties of the LDPE/YPUOH composite films were thoroughly investigated to find out applicablities of the films as functional packaging materials. Although the interfacial interaction between LDPE and YPUOH was relatively weak, LDPE/YPUOH composite films exhibited good dispersion of YPUOH in LDPE, resulting in the enhanced thermal stability with YPUOH loading. Due to the good antibacterial property of as-prepared YPUOH, LDPE/YUOH composite films also showed an excellent antibacterial activity (R) of 99.9% against E. coli. Furthermore, the moisture barrier property of LDPE/YPUOH composite films increased with increasing YPUOH contents. Incorporating the relatively low amount of YPUOH in LDPE resulted in the apparent enhancement in thermal stabilities, antibacterial and moisture barrier properties, which made them promising candidates as a functional filler for packaging materials.

• Polymer(Korea)
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• v.31 no.4
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• pp.283-288
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• 2007

Polymer blends containing poly(acrylonitrile-butadiene-styrene) (ABS) and polycarbonate(PC) (70/30, wt%) with compatibilizer were prepared using twin screw extruder. Compatibilizers were prepared by reactive extrusion with the ABS, maleic anhydride(MAH) and dicumyl peroxide(DCP) using twin screw extruder In the ABS/PC (70/30) blends, tensile strength did not change significantly, but increased from 52.25 to 55.03 MPa when the ABS-g-MAH was added in the amount of 5 phr. From the results of rheological properties, storage modulus of the ABS/PC/ABS-g-MAH blends at low frequencies showed lager value than that of the ABS/PC(70/30) blend. From the results of the morphological properties of the ABS/PC(70/30) blend, it was observed that the drop size of the PC ranged from 1.2 to $1.5\;{\mu}m$ and did not change significantly with the addition of the ABS-g-MAH($1{\sim}10\;phr$). From the results of the storage modulus, complex viscosity, and tensile strength of the ABS/PC (70/30) blends, it is found that the ABS-g-MAH is an effective compatibilizer in the ABS/PC (70/30) blends when the ABS-g-MAH is added in the amount of 5 phr.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3990-3996
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• 2014

Because the physical properties can be decreased when a Nylon 66/glass fiber composite is injected into a mold over $300^{\circ}C$, a systematic study of the thermal history in the case of re-use is needed. Nylon 66/glass fiber extrudates as a function of the extrusion number were prepared using a twin screw extruder at 305/290/273/268/265/$260^{\circ}C$. The chemical structure, thermal properties, melt index, crystal structure, Izod impact strength, and rheological properties were measured by Fourier transform infra-red (FT-IR), melt indexer, DSC, TGA, XRD, Izod impact tester, and dynamic rheometer. The FT-IR spectra indicated that the number of extrusions did not affect the chemical structure. The decrease in molecular weight with increasing extrusion number was confirmed by the melt index and the complex viscosity of extrudates. Based on the DSC and TGA results, the thermal history had no effect on the melting temperature, regardless of the number of extrusions, but the degradation temperature decreased up to $20^{\circ}C$ with increasing extrusion number. The Izod impact strengths of the extrudates were found to decrease with increasing extrusion number. No structural change after extrusion was also confirmed because there was no change in the slope and shape of the G'-G" plot.