Mechanical properties and phase diagrams of alloys of high density polyethylene with some low molecular weight organic compounds

1985 ◽  
Vol 20 (11) ◽  
pp. 3906-3916 ◽  
Author(s):  
B. Hagstr�m
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Phase Diagrams ◽  
Organic Compounds ◽  
High Density Polyethylene ◽  
High Density ◽  
Low Molecular Weight

Influence of Processing Aids and Hydroxyapatite as Fillers on Flow Behaviour and Mechanical Properties of Ultra High Molecular Weight Polyethylene/High Density Polyethylene Composites

2011 ◽  
Vol 471-472 ◽  
pp. 827-832 ◽  
Author(s):  
Mazatusziha Ahmad ◽  
Mat Uzir Wahit ◽  
Mohammed Rafiq Abdul Kadir ◽  
Khairul Zaman Mohd Dahlan
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
High Density Polyethylene ◽  
Flexural Modulus ◽  
High Density ◽  
Compression Moulding ◽  
Biomedical Implant ◽  
Bone Properties ◽  
Ultra High Molecular Weight

In this study, blends of ultra high molecular weight polyethylene/high density polyethylene/polyethylene glycol (UHMWPE/HDPE/PEG) and the composites containing Hydroxyapatite (HA) as reinforcement filler were prepared via single screw extruder nanomixer followed by compression moulding. PEG (2phr) was used as processing aid and HA loadings were varied from 10 to 50 phr. HDPE and PEG were introduced to improve the extrudability of UHMWPE. Rheological behavior was studied via capillary rheometer while flexural and izod impact tests were conducted in order to investigate the mechanical properties of the blends and composites. Melt viscosity of the blends was found to decrease with increasing shear rate indicating a pseudoplastic behaviour. Incorporation of PEG shows a synergism effect on the reduction of blends viscosity. Blend of 40% UHMWPE/ 60% HDPE/ 2 phr PEG was chosen as the optimum blend composition with a balance properties in terms of the mechanical properties and processability. The incorporation of HA fillers from 10 to 50 phr into the blend resulted in the increase of flexural modulus and flexural strength with a slight decline of impact strength values. It can be concluded that the composites having adequate strength and modulus within the range of cancellous bone properties were succesfully developed to be used as biomedical implant devices.

Effect of Low Molecular Weight Ethylene Homopolymer on Structure and Properties of Bimodal High Density Polyethylene

2012 ◽  
Vol 217-219 ◽  
pp. 603-608
Author(s):  
Xing Bo Shi ◽  
Ju Lin Wang ◽  
Xiao Ping Cai
Keyword(s):  
Molecular Weight ◽  
High Density Polyethylene ◽  
Gel Permeation Chromatography ◽  
High Density ◽  
Low Molecular Weight ◽  
Structure And Properties ◽  
Scanning Calorimetry ◽  
Processing Properties ◽  
Positive Effect ◽  
Properties Of Composites

The effect of low molecular weight (LMW) ethylene homoploymer on the structure and properties of bimodal high density polyethylene (HDPE) was studied by blending two commercial bimodal HDPE resins (tandem reactor) with two types of LWM ethylene homopolymer. The molecule weight and molecule weight distribution, crystsallinity, rheological and mechanical properties of composites were characterized by high temperature gel permeation chromatography (HT-GPC), differential scanning calorimetry (DSC), capillary rheometer respectively. For composites of bimodal HDPE and LMW ethylene homopolymer, the polydispersity index (PDI) and crystallinity can be effectively increased when reduce the molecular weight of first reactor in tandem reactor. The viscosity of composites decreases at high shear rate. Increasing of LMW component has a positive effect on processing properties and tensile strength, while makes composites brittle.

Study of the Nature of the Influence of some Oligophosphonates on the Rheological Properties of High-Density Polyethylene

2021 ◽  
Vol 899 ◽  
pp. 606-612
Author(s):  
Abubekir Kh. Shaov ◽  
Asya N. Beslaneeva ◽  
Gennady B. Shustov ◽  
Albina M. Altueva
Keyword(s):  
Molecular Weight ◽  
Rheological Properties ◽  
High Molecular Weight ◽  
High Density Polyethylene ◽  
Functional Group ◽  
High Density ◽  
Low Molecular Weight ◽  
Phosphorus Containing ◽  
Cyclic Compounds

High molecular weight compounds with organophosphorus backbones are usually obtained by polycondensation of phosphorus-containing monomers, leading, most often, to products of low molecular weight at low yields. This fact is explained [1] by several reasons: a decrease in the reactivity of the second functional group of the monomer after the first one has reacted; the possibility of the formation of cyclic compounds; hydrolytic instability of the phosphorus-heteroatom bond (usually P-O, P-N), etc.

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