Fabrication of Particle-Reinforced Polymers with Continuous Gradient Architectures Using Twin Screw Extrusion Process

2004 ◽  
Vol 38 (21) ◽  
pp. 1873-1893 ◽  
Author(s):  
Frederick M. Gallant ◽  
Hugh A. Bruck ◽  
Arun K. Kota
Keyword(s):  
Extrusion Process ◽  
Twin Screw Extrusion ◽  
Reinforced Polymers ◽  
Continuous Gradient ◽  
Screw Extrusion ◽  
Twin Screw

Definition of a JA-2 Equivalent Propellant to be Produced by Continuous Solventless Extrusion

2013 ◽  
Vol 80 (3) ◽  
Author(s):  
Thelma G. Manning ◽  
Joseph Leone ◽  
Martijn Zebregs ◽  
Dinesh R. Ramlal ◽  
Chris A. van Driel
Keyword(s):  
Extrusion Process ◽  
Continuous Manufacturing ◽  
Twin Screw Extrusion ◽  
Extrusion Processing ◽  
Roll Mill ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Ballistic Properties ◽  
Definition Of ◽  
Double Base

In order to eliminate residual solvents in ammunition and to reduce the emissions of volatile organic compounds to the atmosphere, the U.S. Army ARDEC has teamed with TNO in developing a new process for the production of solventless propellant for tank ammunition. To reduce the costs of solventless propellants production, shear roll mill and continuous extrusion processing was investigated. As described in this paper JA-2 a double base propellant cannot be processed without solvent by the extrusion process. An alternative JA-2 equivalent propellant was defined. The aim of this work is to demonstrate the manufacturing of this propellant by solventless continuous twin screw extrusion processing while maintaining gun performance characteristics of conventional JA-2 propellant. This is elucidated by explicitly researching the relationship between interior ballistic properties of the gun propellant and utilizing a continuous manufacturing process. Processing conditions were established, and the propellant was manufactured accordingly. The extruded propellant has the desired properties, which resulted in a comparable gun performance as the conventional JA-2 propellant.

scholarly journals Effect of the Intensive Plasticizing Zone Design on the Effectiveness of Corotating Twin-Screw Extrusion

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Emil Sasimowski ◽  
Łukasz Majewski
Keyword(s):  
Experimental Design ◽  
Rotational Speed ◽  
Extrusion Process ◽  
Empirical Models ◽  
Filling Ratio ◽  
Mixing Zone ◽  
Twin Screw Extrusion ◽  
Screw Extruder ◽  
Screw Extrusion ◽  
Twin Screw

The aim of this study was to investigate the effect of a new intensive plasticizing and mixing screw zone design on the effectiveness of the corotating twin-screw extrusion process for talc-filled polypropylene. The study determined the effect of the angle between the trilobe kneading elements forming the intensive plasticizing and mixing zone of the screws, the screw rotational speed, and the polypropylene/talc filling ratio on the characteristics of the extrusion process in a corotating twin-screw extruder EHP-2x20. The paper describes the experimental design and obtained results as well as the developed empirical models for selected variables of the extrusion process.

Twin Screw Extrusion Process

Extrusion ◽  
2014 ◽  
pp. 111-120 ◽  
Author(s):  
John R. Wagner ◽  
Eldridge M. Mount ◽  
Harold F. Giles
Keyword(s):  
Extrusion Process ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw

Effect of Compatibilizers on Composite Materials of Bio-Ethanol Byproduct-Poly(lacticacid)

2012 ◽  
Vol 204-208 ◽  
pp. 4088-4092
Author(s):  
Ming Ming Zhang ◽  
Xiao Huan Liu ◽  
Chun Peng Wang ◽  
Li Wei Jin
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Composite Materials ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Process Effects ◽  
Properties Of Composites

The blend composite materials of bio-ethanol byproduct-Poly(lactic acid) (PLA) were produced by a twin-screw extrusion process. Effects of bio-ethanol byproduct (BEB) contents and different compatibilizers on properties of composite materials were investigated. The research showed that with the increase of contents of bio-ethanol byproduct, the mechanical properties decreased. The mechanical properties of composites were improved by adding the compatibilizers, especially the polypropylene grafted maleic anhydride (PP-MAH). When the PP-MAH content was 2.5%, the mechanical properties of the composite materials were superior to others.

Simulation Of The Mixing Of Highly Filled Suspensions In The Co-Rotating Twin Screw Extrusion Process

1988 ◽  
Author(s):  
Dilhan M. Kalyon ◽  
Alexandros D. Gotsis ◽  
Costas G. Gogos ◽  
Christos Tsenoglou
Keyword(s):  
Extrusion Process ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw

Ethanol Extraction of Flavonoids from Mungbean Skin after Twin-Screw Extrusion Process

2011 ◽  
Vol 393-395 ◽  
pp. 1203-1211
Author(s):  
Bing Du ◽  
Yan Li Jiao ◽  
Zhi Qiang Huang ◽  
Lian Kai Mao ◽  
Yuan Yuan Fan ◽  
...  
Keyword(s):  
Feeding Rate ◽  
Extrusion Process ◽  
Ethanol Solution ◽  
Extraction Rate ◽  
Twin Screw Extrusion ◽  
Ethanol Extraction ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Process Effects ◽  
Feed Moisture

In order to increase the extraction rate of flavonoids from mungbean skin, twin-screw extrusion process was used as a pretreatment method. After optimizing conditions of twin-screw extrusion process, effects on ethanol extracting flavonoids were studied. Results revealed that the best extrusion conditions were: screw speed at 268r/min, extrusion temperature at 115~120°C, feed moisture at 17% and feeding rate at 726g/min. Under these conditions, the optimum condition for ethanol extraction of flavonoids was: using 38% ethanol solution at a material-liquid ratio of 1:20 at 77.5 °C with 2.5 h. The average extraction rate of flavonoids from mungbean skin was 3.14%, comparing to rate of un-extruded material 2.07%, extraction rate raised by 51.5%. This pretreatment can destroy the density structure of mungbean skin which has great effect on the increase of extraction rate of flavonoids.

A Model for Feeder-Extruder Interactions

1993 ◽  
Vol 115 (1) ◽  
pp. 118-123
Author(s):  
J. H. Conner ◽  
D. I. Bigio
Keyword(s):  
Product Quality ◽  
Extrusion Process ◽  
Theoretical Description ◽  
Transfer Model ◽  
Fluid Composition ◽  
Fluid Element ◽  
Twin Screw Extrusion ◽  
Process Understanding ◽  
Screw Extrusion ◽  
Twin Screw

In the field of plastic extrusion, the accurate feeding of materials to the extrusion process is an important issue. The end product quality is partially dependent upon the extruder receiving feed materials in the correct proportions. Therefore, the understanding of the relationship between the feeder and the extruder is very important. This paper presents and analyzes this relationship. The feeder is usually a separate and distinct item from the extruder. The feed materials and the environmental conditions may affect the flow rate of the reaction or blending process of the extrusion process. The variation of this feed material may cause the quality of the overall product to be beyond an acceptable quality. This paper shows that two feeder parameters, the period and amplitude of the feeder error, affect the composition of the materials throughout the extrusion process. Understanding the effect of these parameters will allow for the overall improvement in product quality. This paper also shows that the extrusion process is able to dampen the error of the feeder. In other words, by mixing a fluid element the average fluid composition will tend towards a nominal value. The fluid composition error associated with the fluid element will decay exponentially. This paper presents two models to describe phenomena described above. The first model is a theoretical description of an idealized mixing process with a time varying feeder error. The second model is an iterative mass transfer model representing a nonintermeshing twin screw extrusion process. An analysis of each of these models will demonstrate how the error of fluid composition reduces as a function of the amount of mixing.

Experimental investigations for preparation of biocompatible feedstock filament of fused deposition modeling (FDM) using twin screw extrusion process

2017 ◽  
Vol 31 (11) ◽  
pp. 1455-1469 ◽  
Author(s):  
Rupinder Singh ◽  
Nishant Ranjan
Keyword(s):  
Fused Deposition Modeling ◽  
Extrusion Process ◽  
Functionally Graded ◽  
Experimental Investigations ◽  
Twin Screw Extrusion ◽  
Fused Deposition ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Deposition Modeling ◽  
Ceramic Fillers

Twin screw extrusion (TSE) is one of the commercially established processes for reinforcement of metallic/nonmetallic/ceramic fillers in polymer matrix for tailor-made applications. In this study, biocompatible feedstock filament has been prepared (in-house) for commercial fused deposition modeling (FDM) setup with biocompatible grade polymers, namely polyvinyl chloride and polypropylene which was reinforced with the hydroxyapatite particles. The process parameters (namely, material composition, rotational speed of TSE, die temperature of TSE, HAp particle grain size, and applied load on TSE) were optimized using Taguchi L18 orthogonal array. In this study, mechanical, thermal, and metallurgical properties have been established, and best-feedstock filament wire for development of partial/complete denture on the FDM with functionally graded surfaces properties has been recommended for future applications.

scholarly journals Free fatty acids in rice bran during its storage after a treatment by twin-screw extrusion to prevent possible rapid hydrolytic rancidity of lipids

DYNA ◽  
2019 ◽  
Vol 86 (208) ◽  
pp. 177-181
Author(s):  
Beatriz Guevara Guerrero ◽  
Alejandro Fernández-Quintero ◽  
Juan Carlos Montero-Montero
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Rice Bran ◽  
Extrusion Process ◽  
Ambient Conditions ◽  
Twin Screw Extrusion ◽  
Time Period ◽  
Screw Extrusion ◽  
Twin Screw ◽  
C 78

This research studied the prevention of hydrolytic rancidity during the storage of rice bran stabilized by an extrusion process. A double screw extruder was used, set at 130° C in the barrel and a rotational speed of the screws programmed at 200 RPM. The moisture content of the bran was adjusted at 20%. The treated bran was stored, using two packing methods (with and without vacuum), at two ambient conditions (18° C – 70 % RH and 30° C - 78% RH) for a period of 8 weeks. The content of free fatty acids (FFA) in the rice bran was observed during the storage time period. The extruded treated rice bran stored at 18° C - 70% RH resulted in lower values of FFA in comparison with the values in the bran kept at 30° C - 78% RH. Vacuum packaging showed a significant disadvantage as compared to packaging without vacuum.

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