Infrared spectrometric determination of catalysts used in the production of high-density polyethylene

1981 ◽  
Vol 53 (14) ◽  
pp. 2232-2234 ◽  
Author(s):  
David R. Battiste ◽  
James P. Butler ◽  
Joe B. Cross ◽  
Max P. McDaniel
Keyword(s):  
High Density Polyethylene ◽  
High Density

Modelling of stresses and strains in two-layer combined materials at their formation

2019 ◽  
Vol 1-2 (97) ◽  
pp. 12-19
Author(s):  
G.M. Koloskova
Keyword(s):  
High Density Polyethylene ◽  
Bottom Layer ◽  
High Density ◽  
Bottom Plate ◽  
Distribution Dynamics ◽  
Polymer Metal ◽  
First Time ◽  
Practical Implications

Purpose: The aim of the represented study was to model the behaviour of two-layer combined material during its manufacturing. Design/methodology/approach: The model of material layers joining by means of calender method is built in LS-DYNA software on the basis of finite element method. Using the developed model the study of stress and strain condition changes is carried out. Numerical modelling was carried out for two types of two-layer combined materials in similar conditions. First combination was of high-density polyethylene top layer and aluminium foil bottom layer. Second combination was of high-density polyethylene top layer and low- density polyethylene bottom layer. Joining materials had equal thicknesses. Findings: During formation of two-layer combined materials the primary strain always occurs at the bottom plate of the bottom layer. However, the maximum plastic strain will be represented for the layer with lower elastic modulus value. At the point of the highest loading applied to the two-layer combined material the elasticity condition is changed to the plasticity one and the yield process is registered. Practical implications: Multi-layer combined materials are some of the most advanced types of materials. The quality of the joining of the layers, the strains and the stresses arising in their manufacturing process are the main causes of low interlayer strength. It leads to easy exfoliation and destruction of the material. The results of the study may be used to improve the quality of multi-layer combined materials. Originality/value: For the first time the model was developed for the determination of strains and stresses arising during the formation of multi-layer combined materials by means of calendering method. The calculations of the stresses and strains distribution dynamics for two-layer combined materials are represented for polymer-metal and polymer-polymer layers combinations. The results of the study may be of interest to specialists in the field of multi-layer combined materials designing and manufacturing.

scholarly journals Determination of physic and mechanical parameters of high-density polyethylene based on relaxation curves due to the presence of hydroxyapatite and ionizing radiation

2018 ◽  
Vol 196 ◽  
pp. 01013
Author(s):  
Stepan Litvinov ◽  
Serdar Yazyev ◽  
Dmitriy Vysokovsky
Keyword(s):  
Ionizing Radiation ◽  
High Density Polyethylene ◽  
High Density ◽  
Cross Linking ◽  
Mechanical Parameters ◽  
Polymer Molecules ◽  
Material Resources ◽  
Definition Of ◽  
Relaxation Curves

Relatively low physical and mechanical parameters of polymers negatively affect the possibility of using this material everywhere. There are ways to improve the elastic and rheological characteristics of some varieties of polymers: addition of additives and irradiation with ionizing radiation. However, these methods can lead both to the cross-linking of polymer molecules with the improvement of its parameters, and to its destruction. In this article shown the theoretical definition of physic and mechanical parameters of high-density polyethylene by known stress relaxation curves, and a comparison of the experimental data of high-density polyethylene (HDPE) with the data obtained theoretically, which, in turn, saves material resources and man-hours for the experiment and its subsequent analysis.

Sign in / Sign up

Export Citation Format

Share Document