scholarly journals The Effect of Recycling on Wood-Fiber Thermoplastic Composites

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1750
Author(s):  
Luísa Rosenstock Völtz ◽  
Irangeli Di Guiseppe ◽  
Shiyu Geng ◽  
Kristiina Oksman
Keyword(s):  
Fiber Length ◽  
Interfacial Adhesion ◽  
Processing Time ◽  
Wood Fiber ◽  
Extrusion Process ◽  
Thermoplastic Composites ◽  
Wood Fibers ◽  
Screw Extruder ◽  
Twin Screw ◽  
Number Of Passes

The aim of this study was to investigate the effect of recycling on polypropylene (PP) and wood-fiber thermoplastic composites (WPCs) using a co-rotating twin-screw extruder. After nine extrusion passes microscopy studies confirmed that the fiber length decreased with the increased number of recycling passes but the increased processing time also resulted in excellent dispersion and interfacial adhesion of the wood fibers in the PP matrix. Thermal, rheological, and mechanical properties were studied. The repeated extrusion passes had minimal effect on thermal behavior and the viscosity decreased with an increased number of passes, indicating slight degradation. The recycling processes had an effect on the tensile strength of WPCs while the effect was minor on the PP. However, even after the nine recycling passes the strength of WPC was considerably better (37 MPa) compared to PP (28 MPa). The good degree of property retention after recycling makes this recycling strategy a viable alternative to discarding the materials. Thus, it has been demonstrated that, by following the most commonly used extrusion process, WPCs can be recycled several times and this methodology can be industrially adapted for the manufacturing of recycled products.

Mechanical and thermal characterization of grafted PP-NCC nanocomposites

2019 ◽  
pp. 089270571987822
Author(s):  
Saud Aldajah ◽  
Mohammad Y Al-Haik ◽  
Waseem Siddique ◽  
Mohammad M Kabir ◽  
Yousef Haik
Keyword(s):  
Thermal Properties ◽  
Interfacial Adhesion ◽  
Thermal Characterization ◽  
Mechanical And Thermal Properties ◽  
Screw Extruder ◽  
Scanning Calorimetry ◽  
Three Point Bending ◽  
Twin Screw ◽  
Thermal Stability Of

This study reveals the enhancement of mechanical and thermal properties of maleic anhydride-grafted polypropylene (PP- g-MA) with the addition of nanocrystalline cellulose (NCC). A nanocomposite was manufactured by blending various percentages of PP, MA, and NCC nanoparticles by means of a twin-screw extruder. The influence of varying the percentages of NCC on the mechanical and thermal behavior of the nanocomposite was studied by performing three-point bending, nanoindentation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy tests. The novelty of this study stems on the NCC nanoparticles and their ability to enhance the mechanical and thermal properties of PP. Three-point bending and nanoindentation tests revealed improvement in the mechanical properties in terms of strength, modulus, and hardness of the PP- g-MA nanocomposites as the addition of NCC increased. SEM showed homogeneity between the mixtures which proved the presence of interfacial adhesion between the PP- g-MA incorporated with NCC nanoparticles that was confirmed by the FTIR results. DSC and TGA measurements showed that the thermal stability of the nanocomposites was not compromised due to the addition of the coupling agent and reinforced nanoparticles.

Effect of different extrusion methods on physicochemical properties and qualities of noodles based on rice flour

2021 ◽  
pp. 108201322110692
Author(s):  
Nispa Seetapan ◽  
Bootsrapa Leelawat ◽  
Nattawut Limparyoon ◽  
Rattana Yooberg
Keyword(s):  
Moisture Content ◽  
Rice Flour ◽  
Extrusion Process ◽  
Scanning Electron Micrographs ◽  
Twin Screw Extruder ◽  
Capillary Rheometer ◽  
Screw Extruder ◽  
Scanning Calorimetry ◽  
Twin Screw ◽  
Thermomechanical Processes

Rice noodles have been manufactured in the food industry using different extrusion methods, such as traditional and modern extrusions, which affect the noodle structure and qualities. Therefore, the effects of the extrusion process on qualities of rice noodles using the same blend of rice flour and crosslinked starch were evaluated. In this study, a capillary rheometer was used as an alternative approach to simulate the traditional extrusion method in which the noodles are obtained by continuously pressing the pregelatinized noodle dough through a die. For modern extrusion, a twin-screw extruder was employed to obtain the noodles in a one-step process. The optimal range of moisture content used in the formulation was studied. Upon cooking, the noodles showed a decrease in cooking time and cooking loss with increasing moisture content in the formulation. All cooked noodles showed comparable tensile strength, but those extruded by a twin-screw extruder had substantially greater elongation. Scanning electron micrographs revealed that the noodles prepared using the extruder had a denser starch matrix, while those obtained from a capillary rheometer showed the aggregation of starch fragments relevant to the existence of starch gelatinization endotherm from differential scanning calorimetry. This indicated that the extrusion process using the twin-screw extruder provided a more uniform starch transformation, i.e., more starch granule disruption and gelatinization, thus giving the noodles a more coherent structure and better extensibility after cooking. The obtained results suggested that different thermomechanical processes used in the noodle industry gave the extruded rice noodles different qualities respective to their different microstructures.

Optimization of nutrient retention in whole flours extruded from cowpea biofortified grain

2021 ◽  
Vol 24 ◽  
Author(s):  
Jorge Minoru Hashimoto ◽  
Jéssica Pinheiro Mendes Sampaio ◽  
Luís José Duarte Franco ◽  
Elizabeth Harumi Nabeshima ◽  
Kaesel Jackson Damasceno e Silva
Keyword(s):  
Moisture Content ◽  
Rotation Speed ◽  
Nutrient Retention ◽  
Magnesium Content ◽  
Extrusion Process ◽  
Screw Extruder ◽  
Twin Screw ◽  
Iron And Zinc ◽  
Copper Zinc ◽  
Extruded Products

Abstract Whole flour of cowpea grains of the cultivar BRS Tumucumaque biofortified in iron and zinc were processed in a co-rotating twin-screw extruder Clextral HT 25. A central rotational composite design 23, combining temperature (from 86.4 to 153.6 °C), screw rotation speed (from 163.6 to 836.4 rpm) and moisture content (from 16.6% to 23.4%), was used to assess the effects on flour constituents. The three variables significantly affected (p < 0.05) the levels of protein and copper in the extrudates. The reactions of the extrusion process caused a decrease in the levels of proteins and an increase in the levels of copper, zinc and potassium, and these amounts were accentuated as the values of the process variables approached those of the central point region. Extreme conditions at high rotational screw speeds combined with low moisture content reduced the magnesium content, at the opposite end of the values for these two variables, the intensity of the reduction was lower. In the analysis of global desirability, it was found that the extrusion condition at 112.6 °C, 587.4 rpm and 23.4% moisture provided the highest nutrient retention. The levels of iron and zinc remained above 60 and 40 mg kg-1, respectively, in extruded products.

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.

Viscoelastic, thermal, and morphological properties of nanocomposites based on modified PVA using a twin-screw melt extrusion process

2019 ◽  
Vol 33 (11) ◽  
pp. 1555-1568
Author(s):  
B Rajeswari ◽  
N Malarvizhi ◽  
Dhanasekaran Prakash ◽  
Sellamuthu N Jaisankar
Keyword(s):  
Polymer Nanocomposites ◽  
Flow Behavior ◽  
Extrusion Process ◽  
Morphological Properties ◽  
Screw Extruder ◽  
Weight Percentage ◽  
Bonding System ◽  
Increase With Increase ◽  
Twin Screw ◽  
Melting Endotherm

Melt polymer nanocomposites were prepared using polyvinyl alcohol (PVA) with the different weight percentage of calcined clays (CCs) in a twin-screw extruder at 210°C and 70 r min−1 for 8 min. Bentonite was surface functionalized with benzidine using dilute hydrochloric acid at 60°C and calcined at 600°C for 6 h. The CCs were incorporated into the PVA matrix to study their morphology and rheological properties. The melt viscosities of the composites were measured by the cone-plate rheometer, the rheogram show non-Newtonian and thixotropic flow behavior. Scanning electron microscope confirmed the degree of exfoliated nanocomposites. The polymer and functionalized nanoclay interactions were reflected in the enhancement of thermal stability and mechanical properties. The melting endotherm temperature ( T m) and glass transition temperature ( T g) of the nanocomposites tend to increase with increase in weight percentage of the calcined nanoclays. Thermal properties show that addition of calcined nanoclays would improve the thermal decomposition temperatures from 295°C to 307°C when CC content was 2 wt% in covalent or ionic bonding system.

Investigation on the uniformity of high-density polyethylene/wood fiber composites in a twin-screw extruder

2009 ◽  
Vol 113 (4) ◽  
pp. 2081-2089 ◽  
Author(s):  
Jingjing Zhang ◽  
Chul B. Park ◽  
Ghaus M. Rizvi ◽  
Hanxiong Huang ◽  
Qingping Guo
Keyword(s):  
High Density Polyethylene ◽  
Wood Fiber ◽  
Fiber Composites ◽  
High Density ◽  
Twin Screw Extruder ◽  
Screw Extruder ◽  
Twin Screw

The Reinforcement of Acicular Wollastonite on Polypropylene

2010 ◽  
Vol 92 ◽  
pp. 283-288 ◽  
Author(s):  
Ming Shan Yang
Keyword(s):  
Electron Microscope ◽  
Interfacial Adhesion ◽  
Screw Extruder ◽  
Feeding Method ◽  
Reinforcing Effect ◽  
Comprehensive Properties ◽  
Different Types ◽  
Twin Screw ◽  
Pp Composites ◽  
Scanning Electron

The wollastonite/PP composites were manufactured by twin-screw extruder and the effects of compatabilizer, feeding method and screw configuration on the properties of wollastonite/PP composites were investigated in this paper. The dispersion of fibrous wollastonite in PP matrix was determined by scanning electron microscope (SEM). The results showed that the strength, toughness and flowability of the composite were simultaneously guaranteed by using three different types of PP resins, and the interfacial adhesion was improved greatly by adding the compatabilizer of PP-g-MAH, which increases the comprehensive properties of wollastonite/PP composite. The fibrous dispersion of wollastonite in PP matrix was achieved by using of side feeding and the weak-shear screw configuration, which reaches the good reinforcing effect.

Study on Modified Wood Fiber/Recycled Plastic HDPE Composites

2012 ◽  
Vol 253-255 ◽  
pp. 326-329
Author(s):  
Han Yan
Keyword(s):  
Silane Coupling Agent ◽  
Organic Molecules ◽  
Wood Fiber ◽  
Hollow Structure ◽  
Hollow Fibers ◽  
Wood Fibers ◽  
Screw Extruder ◽  
Silane Coupling ◽  
Modified Wood ◽  
Recycled Hdpe

The effect on stripped the wood fiber with organic molecules inserting pretreatment to recycled HDPE plastic was researched. Organic molecules inserting wood fiber has layered hollow structure by screw extruder and silane coupling agent molecules can insert into hollow fibers. The results show that composites with stripped wood fibers have better mechanical properties than unstripped composites. SEBS elastomer treatment can further enhance the toughness of the wood-plastic composites.

Mechanical Properties of Barley Straw/HDPE Composites Produced with Extrusion Process

2021 ◽  
Vol 410 ◽  
pp. 593-598
Author(s):  
Anton M. Kuzmin ◽  
Nadir Ayrilmis ◽  
Vladimir N. Vodyakov
Keyword(s):  
Mechanical Properties ◽  
Polymer Composite ◽  
Physical And Mechanical Properties ◽  
Extrusion Process ◽  
Barley Straw ◽  
Processing Temperature ◽  
Screw Extruder ◽  
Wood Polymer ◽  
Twin Screw ◽  
Wood Polymer Composite

This paper is devoted to the study of the technological process for the production of tape from polyethylene and wood-polymer composite by extrusion. At the first stage, the wood-polymer composite granulate was obtained on a co-rotating twin-screw extruder. The tape was made on a Rheomex 19/25 PolyLab OS single-screw extruder with a barrel length L/D = 25. The processing temperature of the wood-polymer composite was in the range of 145 ... 160°C. The tensile strength and elasticity modulus in tension, water absorption per day and density were investigated for the developed wood-polymer composite and polyethylene. It has been found out that for the developed wood-polymer composite, the strength and elastic modulus along the stretch direction increase by 11% and 6%, respectively. Orientation stretching has a significant effect on the physical and mechanical properties of wood-polymer composites.

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