Dynamic mechanical evidence for the glass transition of high density polyethylene

1976 ◽  
Vol 16 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Neil A. Paauwe ◽  
Jack R. Knox
Keyword(s):  
Glass Transition ◽  
High Density Polyethylene ◽  
High Density ◽  
Dynamic Mechanical

Improvement of the Properties of Polyethylene with Chlorinated Polyethylene (CPE)

2003 ◽  
Vol 11 (2) ◽  
pp. 115-122
Author(s):  
Kálmán Marossy ◽  
Pál Bárczy
Keyword(s):  
High Density Polyethylene ◽  
Industrial Applications ◽  
Mechanical Tests ◽  
High Density ◽  
Structural Units ◽  
Chlorinated Polyethylene ◽  
X Ray ◽  
Dynamic Mechanical ◽  
X Ray Scattering ◽  
Multiphase Systems

Blends of high density polyethylene (HDPE) and chlorinated polyethylene (CPE) have been tested across the whole concentration range. Polyethylene is used to modify the properties of CPE in the elastomer industry, but modification of the properties of polyethylene with CPE is still not usual. Conventional mechanical tests and dynamic mechanical tests were carried out. The blends were found to be multiphase systems of excellent technological compatibility. Between 10 and 15% by weight CPE increased the modulus of polyethylene. X-ray scattering studies showed that the blends contained structural units not present either in the polyethylene or in the CPE. The blends were melt processable and may have industrial applications, too.

Advanced properties of composites of recycled high-density polyethylene and microfibers of sugarcane bagasse

2017 ◽  
Vol 52 (7) ◽  
pp. 867-876 ◽  
Author(s):  
Sibele Piedade Cestari ◽  
Gerson Alberto Valencia Albitres ◽  
Luis C Mendes ◽  
Volker Altstädt ◽  
Jair Braga Gabriel ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Dynamic Mechanical Analysis ◽  
Sugarcane Bagasse ◽  
High Density Polyethylene ◽  
Building Materials ◽  
Mechanical Analysis ◽  
High Density ◽  
Wide Angle ◽  
X Ray ◽  
Dynamic Mechanical

Aiming to systematically convert post-consumer plastics in building materials, we compounded recycled high-density polyethylene and sugarcane bagasse. We ranged the polymer/filler ratio from 100/0 to 60/40, and assessed the properties using optical microscopy, water absorption test, adhesion by tape test, low-field nuclear magnetic resonance, dynamic-mechanical analysis, and wide-angle X-ray diffractometry. The optical microscopy of the triturated bagasse showed the reduced and heterogeneous fiber sizes. The absorption and adhesion test showed that the polymer more heavily filled with bagasse can better absorb and anchor paint with organic solvent base. The dynamic-mechanical analysis and wide-angle X-ray diffractometry led us to believe that the bagasse fibers somehow structured the amorphous region amongst the crystallized lamellae of the polymeric matrix. We concluded that these composites have interesting properties to produce building materials.

scholarly journals Effects of Expandable Graphite at Moderate and Heavy Loadings on the Thermal and Electrical Conductivity of Amorphous Polystyrene and Semicrystalline High-Density Polyethylene

Applied Nano ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 31-45
Author(s):  
Panagiotis A. Klonos ◽  
Lazaros Papadopoulos ◽  
Dimitra Kourtidou ◽  
Konstantinos Chrissafis ◽  
Vasileios Peoglos ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Glass Transition ◽  
High Density Polyethylene ◽  
Laser Flash ◽  
Filler Loading ◽  
High Density ◽  
Heat Capacity Change ◽  
Expandable Graphite ◽  
Thermal Transitions ◽  
Scanning Calorimetry

In this work, we prepared and investigated two series of polymer composites, wherein the matrix was either an amorphous polystyrene (PS) or a semicrystalline high-density polyethylene (HDPE) filled with expandable graphite (EGr) at relatively high loadings within the range 5–55 wt %. For the investigation we employed a thermogravimetric analysis and differential scanning calorimetry to assess the thermal transitions and evaluate the various polymer fractions (crystalline (CF), mobile (MAF) and rigid amorphous (RAF)) in addition to broadband dielectric spectroscopy and a laser flash analysis to evaluate the EGr effects on electrical conductivity, σ, and thermal conductivity, λ, respectively. In PS, EGr was found to impose an increase of the glass transition temperature and a systematic decrease of the corresponding heat capacity change. The latter was rationalized in terms of the formation of an interfacial RAF. No glass transition was recorded for HDPE whereas the fillers increased the CF moderately. As expected, σ increased with the filler loading for both matrices, up to 10−3–10−2 S/cm, resulting in a conductive percolation threshold for electrons at > 8 wt % EGr. Simultaneously, the λ of PS and HDPE were strongly increased, from 0.13 and 0.38 W·K–1·m–1 up to 0.55 and ~2 W·K–1·m–1, respectively. λ demonstrated an almost linear EGr loading dependence whereas the semicrystalline composites exhibited a systematically higher λ.

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