Effect of Carbon Fillers in Ultrahigh Molecular Weight Polyethylene Matrix Prepared by Twin-Screw Extrusion

This article presents the effect of twin-screw extrusion processing parameters, including temperature and rotational speed of screws, on the structure and properties of four grades of polylactide (PLA). To evaluate the critical processing parameters for PLA and the possibilities for oxidative and thermomechanical degradation, Fourier-transform infrared spectroscopy (FT-IR), oscillatory rheological analysis, and differential scanning calorimetry (DSC) measurements were used. The influence of degradation induced by processing temperature and high shearing conditions on the quality of the biodegradable polyesters with different melt flow indexes (MFIs)was investigated by color analysis within the CIELab scale. The presented results indicate that considering the high-temperature processing of PLA, the high mass flow index and low viscosity of the polymer reduce its time of residence in the plastifying unit and therefore limit discoloration and reduction of molecular weight due to the degradation process during melt mixing, whereas the initial molecular weight of the polymer is not an essential factor.

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Effect of HA Content on Mechanical Properties of Hot Drawn HA/UHMWPE Nanocomposites for Bone Substitutes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.334-335.701 ◽

2007 ◽

Vol 334-335 ◽

pp. 701-704

Author(s):

Li Ming Fang ◽

Yang Leng ◽

Ping Gao

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Ultrahigh Molecular Weight Polyethylene ◽

Tensile Tests ◽

Bone Substitutes ◽

Nano Particles ◽

Twin Screw Extrusion ◽

Screw Extrusion ◽

Twin Screw ◽

Hot Drawing

Hydroxyapatite reinforced ultrahigh molecular weight polyethylene (HA/UHMWPE) nanocomposites with HA volume fraction 0.1~0.5 are processed by twin-screw extrusion compounding and compression molding followed by hot drawing. SEM micrographs show that HA nano-particles are homogeneously dispersed in the highly oriented UHMWPE inter-fibrils. Tensile tests show that the modulus increases, while the strength and ductility decrease, with the increase of HA content. A good combination of mechanical properties can be obtained in the composite with HA nano-particles volume fraction 0.3.

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Development of Polymer Composite Materials Based on Ultrahigh-Molecular Weight Polyethylene and Carbon Fillers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.945.362 ◽

2019 ◽

Vol 945 ◽

pp. 362-368 ◽

Cited By ~ 1

Author(s):

O.V. Gogoleva ◽

P.N. Petrova ◽

E.S. Kolesova

Keyword(s):

Molecular Weight ◽

Wear Resistance ◽

Composite Materials ◽

Polymer Composite ◽

Carbon Fibers ◽

Ultrahigh Molecular Weight Polyethylene ◽

Polymer Composite Materials ◽

Ultrahigh Molecular Weight ◽

Carbon Fillers ◽

Properties Of Composites

The present study investigates the influence of carbon fibers of LO-1-12N/40 brand and modified carbon fibers of "Belum" brand on performance properties and structure of polymer composite materials based on UHMWPE of Gur-4150 grade. It has been established that introduction of both modified carbon fibers and LO-1-12N/40 carbon fiber in an amount of from 1 to 10 wt.% into the polymer matrix does not lead to significant changes in stress-strain properties of composites compared to the starting polymer. It is shown that the wear resistance of the obtained materials is significantly increased when filling with 5 wt.% carbon fibers of "Belum" brand. The rate of mass wear of polymer composite materials is reduced by 3.3 times; the friction coefficient of PCM is lowered by 3.5 times relative to the starting polymer.

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