Pre-Fibrillation of Pulps to Manufacture Cellulose Nanofiber Reinforced High-Density Polyethylene using the Dry-Pulp Direct Kneading Method

2021 ◽  
Author(s):  
Yuko Igarashi ◽  
Akihiro Sato ◽  
Hiroaki Okumura ◽  
Fumiaki Nakatsubo ◽  
Takashi Kuboki ◽  
...  
Keyword(s):  
High Density Polyethylene ◽  
Coefficient Of Thermal Expansion ◽  
Tensile Modulus ◽  
Cellulose Fibers ◽  
High Density ◽  
Cellulose Nanofiber ◽  
Feed Material ◽  
Alkenyl Succinic Anhydride ◽  
Melt Compounding ◽  
Kneading Method

Abstract The dry-pulp direct-kneading method is an industrially viable, low-energy process to manufacture cellulose nanofiber (CNF) reinforced polymer composites, where chemically modified pulps can be nanofibrillated and dispersed uniformly in the polymer matrix during melt-compounding. In this study, cellulose fibers with different sizes, ranging from surface-fibrillated pulps with 20 µm in width to fine CNFs with 20 nm in width were prepared from softwood bleached kraft pulps (NBKPs) using a refiner and high-pressure homogenizer (HPH). These cellulose fibers were modified with alkenyl succinic anhydride (ASA), and then dried. The dried ASA-treated cellulose fibers were used as a feed material for melt-compounding in the dry-pulp direct kneading method to fabricate CNF reinforced high-density polyethylene (HDPE). When surface-fibrillated pulps were employed as a feed material, the pulps were nanofibrillated and dispersed uniformly in the HDPE matrix during the melt-compounding, and the composites had much better properties (i.e., much higher tensile modulus and strength and much lower coefficient of thermal expansion) than the composites produced using the pulps without pre-fibrillation. However, when CNFs were used as a feed material, the CNFs were shortened and agglomerated during the melt-compounding, thus deteriorating the properties of the composites. The study concludes that the pre-fibrillation of pulps had a significant impact on the morphology and properties of the composites. Unexpectedly, the surface-fibrillated pulp, which can be produced cost-effectively using a refiner at an industry scale, was a more suitable form than the CNF as a feed material for melt-compounding in the dry-pulp direct kneading method.

Evaluation of the Aging Behavior of High Density Polyethylene in Thermal Oxidative Environment by Principal Component Analysis

2017 ◽  
Vol 727 ◽  
pp. 447-449 ◽  
Author(s):  
Jun Dai ◽  
Hua Yan ◽  
Jian Jian Yang ◽  
Jun Jun Guo
Keyword(s):  
Principal Component Analysis ◽  
Impact Strength ◽  
High Density Polyethylene ◽  
Tensile Modulus ◽  
Principal Component ◽  
Component Analysis ◽  
High Density ◽  
Aging Behavior ◽  
Data Set ◽  
The Impact

To evaluate the aging behavior of high density polyethylene (HDPE) under an artificial accelerated environment, principal component analysis (PCA) was used to establish a non-dimensional expression Z from a data set of multiple degradation parameters of HDPE. In this study, HDPE samples were exposed to the accelerated thermal oxidative environment for different time intervals up to 64 days. The results showed that the combined evaluating parameter Z was characterized by three-stage changes. The combined evaluating parameter Z increased quickly in the first 16 days of exposure and then leveled off. After 40 days, it began to increase again. Among the 10 degradation parameters, branching degree, carbonyl index and hydroxyl index are strongly associated. The tensile modulus is highly correlated with the impact strength. The tensile strength, tensile modulus and impact strength are negatively correlated with the crystallinity.

scholarly journals Chemical Modifications of Continuous Aramid Fiber for Wood Flour/High-Density-Polyethylene Composites with Improved Interfacial Bonding

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 236
Author(s):  
Wanyu Liu ◽  
Yue Li ◽  
Shunmin Yi ◽  
Limin Wang ◽  
Haigang Wang ◽  
...  
Keyword(s):  
High Density Polyethylene ◽  
Wood Flour ◽  
Tensile Modulus ◽  
High Density ◽  
Aramid Fiber ◽  
Chemical Modifications ◽  
Plastic Composites ◽  
Vinyl Triethoxysilane ◽  
Extrusion Method ◽  
Polyethylene Composites

To expand the use of wood plastic composites in the structural and engineering constructions applications, continuous aramid fiber (CAF) with nondestructive modification was incorporated as reinforcement material into wood-flour and high-density-polyethylene composites (WPC) by extrusion method with a special die. CAF was treated with dopamine (DPA), vinyl triethoxysilane (VTES), and DPA/VTES, respectively. The effects of these modifications on compatibility between CAF and WPCs and the properties of the resulting composites were explored. The results showed that compared with the original CAF, the adhesion strength of DPA and VTES combined modified CAF and WPCs increased by 143%. Meanwhile, compared with pure WPCs, CAF after modification increased the tensile strength, tensile modulus, and impact strength of the resulting composites by 198, 92, and 283%, respectively.

scholarly journals Designing cellulose nanofiber surface for high density polyethylene reinforcement

Cellulose ◽  
2018 ◽  
Vol 25 (6) ◽  
pp. 3351-3362 ◽  
Author(s):  
Hiroyuki Yano ◽  
Haruo Omura ◽  
Yoko Honma ◽  
Hiroaki Okumura ◽  
Hironari Sano ◽  
...  
Keyword(s):  
High Density Polyethylene ◽  
High Density ◽  
Cellulose Nanofiber

Influence of Thermal Ratcheting on the Creep and Mechanical Properties of High-Density Polyethylene

2019 ◽  
Vol 141 (4) ◽  
Author(s):  
Rahul Palaniappan Kanthabhabha Jeya ◽  
Abdel-Hakim Bouzid
Keyword(s):  
Creep Strain ◽  
High Density Polyethylene ◽  
Coefficient Of Thermal Expansion ◽  
Creep Property ◽  
High Density ◽  
Steady Creep ◽  
Thermal Cycles ◽  
Ratcheting Strain ◽  
Thermal Ratcheting ◽  
The Impact

Abstract The objective of this research is to describe the consequence of thermal ratcheting on the long-term creep property of the high-density polyethylene (HDPE) material. The thermal ratcheting phenomenon increases significantly the creep strain of HDPE. The magnitude of the creep strain of HDPE increases by 8% after just 20 thermal cycles between 28 and 50 °C. The creep modulus, which is inversely proportional to the creep strain, depletes further under thermal ratcheting. Both the properties change significantly with the number of thermal cycles. The coefficient of thermal expansion (CTE) of HDPE varies with the applied compressive load, with successive thermal cycles, and with the thermal ratcheting temperature. The impact of thermal ratcheting diminishes with an increase in initial steady creep exposure time period, but still the magnitude cumulative deformation induced is noteworthy. The magnitude of growth in creep strain drops from 8% to 2.4% when thermal ratcheting is performed after 1 and 45 days of steady creep, respectively. There is a notable change in the thickness of the material with each heating and cooling cycle even after 45 days of creep; however, the thermal ratcheting strain value drops by 80% in comparison with the thermal ratcheting strain after 1 day of creep and under similar test conditions.

Mechanical Properties of Selected Types Thermoplastic Materials Modified by High Doses of Ionizing Beta Radiation under Thermal Stress

2017 ◽  
Vol 756 ◽  
pp. 35-43
Author(s):  
Martin Bednarik ◽  
Adam Skrobak ◽  
Vaclav Janostik
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Thermal Stress ◽  
High Density Polyethylene ◽  
Thermal Loading ◽  
Tensile Modulus ◽  
High Density ◽  
Beta Radiation ◽  
Measurement Results ◽  
High Doses

This study deals with the effect of high doses of ionizing beta radiation (132, 165 and 198 kGy) on mechanical properties (tensile strength, tensile modulus and elongation) of low and high density polyethylene under thermal loading. The measurement results of this study indicate that with an increasing dose of radiation grows tensile strength and modulus of low and high density polyethylene. For all examined materials were also observed changes in elongation.

Performance characteristics of polyethylene/old corrugated container composites reinforced with carbon nanotubes

2016 ◽  
Vol 51 (18) ◽  
pp. 2665-2673 ◽  
Author(s):  
Behzad Kord ◽  
Mehdi Roohani
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
High Density Polyethylene ◽  
Analysis Data ◽  
High Density ◽  
Scanning Calorimetry ◽  
Polyethylene Matrix ◽  
Melt Compounding ◽  
The Impact ◽  
Thermal Stability Of

The physical, mechanical, thermal, and flammability properties of high-density polyethylene/old corrugated container composites reinforced with carbon nanotubes are presented in this study. High-density polyethylene/old corrugated container composites with different loadings of carbon nanotube (0, 1, 3, and 5 phc) were prepared by melt compounding followed by injection molding. Results indicated that the incorporation of carbon nanotube into high-density polyethylene, significantly improved the mechanical properties of the composites. The tensile and flexural properties achieved the maximum values when 3 phc carbon nanotube was added. Meanwhile, the impact strength of the composites progressively decreased with increasing carbon nanotube content. Furthermore, the water absorption and thickness swelling of the samples remarkably reduced with the addition of carbon nanotube. From thermogravimetric analysis data, the presence of carbon nanotube could enhance the thermal stability of the composites, especially the maximum weight loss rate temperature and also the better char residual was obtained at high loading level of carbon nanotube. Simultaneous differential scanning calorimetry thermograms revealed that the thermal degradation temperatures for the samples with carbon nanotube were much higher than those made without carbon nanotube. Moreover, it was found that the addition of carbon nanotube results in a significant enhancement in flame retardancy of the composites. Morphological observations showed that the nanoparticles were predominantly dispersed uniformly within the high-density polyethylene matrix.

Reinforcing Effect of Montmorillonite Nanoclay on Mechanical Properties of High Density Polyethylene Nanocomposites

2014 ◽  
Vol 591 ◽  
pp. 60-63 ◽  
Author(s):  
N. Venkatesan ◽  
G.B. Bhaskar ◽  
Kaliyaperumal Pazhanivel ◽  
K. Poyyathappan
Keyword(s):  
Mechanical Properties ◽  
High Density Polyethylene ◽  
Solid Material ◽  
High Density ◽  
Polymer Materials ◽  
Good Surface ◽  
Melt Compounding ◽  
Standard Specimens ◽  
Twin Screw ◽  
Good Surface Finish

In recent years, many researches focused on the polymer materials to study the characteristics and to enhance the mechanical properties of the nanocomposites in order to understand the factors which lead to the desired dispersion of nanoclay in the polymer matrix. The samples used in this work were prepared through melt compounding, using high-density polyethylene and organo-modified clay of montmorillonite (MMT). During manufacturing of MMT/HDPE nanocomposites, a silane modifier and polyethylene grafted with maleic anhydride (compatibilizer) were added to get good surface finish and to act as bonding agent respectively. In addition, the compatibilizer will help in attaining better intercalation. Using a Plastograph-Mixer through twin-screw extruder, the high density polyethylene and different weight percentages (0, 1, 2, 3, 4 wt. %) of MMT are mixed and subsequently the composite is produced in the form of solid material. ASTM standard specimens for various tests are produced using injection molding machine with respective dies. The prepared experimental specimens for various tests like tensile, flexural, impact and shore-hardness are tested for its respective strengths. From this investigation, it is concluded that the addition of MMT nanoclay in HDPE has significantly influenced the mechanical properties of the composites.

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