Dilatometric Determination of Polymer Compatibility

1963 ◽  
Vol 36 (3) ◽  
pp. 668-674 ◽  
Author(s):  
G. M. Bartenev ◽  
G. S. Kongarov
Keyword(s):  
Experimental Error ◽  
Linear Expansion ◽  
Volume Ratio ◽  
Glass Temperature ◽  
Polymer Mixtures ◽  
Polymer Compatibility ◽  
Coefficient Of Linear Expansion

Abstract 1. The temperature contraction curves for rubbery polymer mixtures define the degree of compatibility of these polymers only when the glass temperatures are not close to the same. 2. Mixtures of obviously incompatible polymers display several glass temperatures (according to the number of polymers in the mixture). The values of these temperatures coincide with the glass temperatures of the pure polymers and do not depend on the ratio of the polymers in the mixture. 3. Mixtures of compatible polymers have a single glass temperature which changes linearly with the volume ratio of the polymers. 4. The coefficient of linear expansion (contraction) of all polymer mixtures follows the additivity law within the visible limits of experimental error from sample to sample.

scholarly journals Calculation of changes in specific volumes of Fe – C system alloys depending on carbon content and temperatures

2019 ◽  
Vol 62 (8) ◽  
pp. 627-631 ◽  
Author(s):  
D. I. Gabelaya ◽  
Z. K. Kabakov ◽  
M. A. Mashchenko
Keyword(s):  
Specific Volume ◽  
Linear Expansion ◽  
Equilibrium Diagram ◽  
Continuous Cast ◽  
Equilibrium System ◽  
A New Technique ◽  
Coefficient Of Linear Expansion ◽  
Carbon Concentrations ◽  
Specific Volumes

The work presents a new technique for determining the temperature dependence of the alloy specific volumes in Fe – C equilibrium system based on known from the literature calculated and empirical dependence for account of the phases’ specific volumes. These data were based on the independent reports of S.F. Yuryev and were obtained for temperatures below 1200 °C. When using these forms at temperatures above 1200 °C, the specific volume of austenite exceeds specific volume of ferrite. However, it is known that austenite has the smallest specific volume among all phases of the Fe – C system. In this regard, in the field of high temperatures, it is proposed to use other dependences that do not contradict the physics of polymorphic and phase transformations in this system. Thus the authors have obtained the general expressions for calculating the alloys’ specific volumes separately for three intervals of carbon concentrations in which the change in shares of the temperature phases are calculated according to Fe – C equilibrium diagram using the lever relation. As an example, results of the calculated determination of specific volumes of alloys with carbon vontent of 0.05, 0.13 and 0.33 % in the temperature range of 20 – 1600 °C are considered. The presented results are compared with the results obtained with the help of the phase diagram calculation package JMatPro®, on the basis of which the adequacy of the proposed calculation method was established. The developed technique can be used to calculate not only specific volumes of alloys, but also their density and coefficient of linear expansion depending on temperature and carbon concentration. It is the basis for the correct use of methods for determining the size of continuous cast billets due to shrinkage in order to correctly configure the equipment of continuous casting machines.

Stoichiometric Determination of Graphite Intercalation Compounds Using Rutherford Backscatiering Spectrometry

1983 ◽  
Vol 27 ◽  
Author(s):  
L. Salamanca-Riba ◽  
B.S. Elman ◽  
M.S. Dresselhaus ◽  
T. Venkatesan
Keyword(s):  
Experimental Error ◽  
Rutherford Backscattering Spectrometry ◽  
Rutherford Backscattering ◽  
Intercalation Compounds ◽  
Graphite Intercalation Compounds ◽  
X Ray ◽  
Donor And Acceptor ◽  
Graphite Intercalation ◽  
Non Destructive

ABSTRACTRutherford backscattering spectrometry (RBS) is used to characterize the stoichiometry of graphite intercalation compounds (GIC). Specific application is made to several stages of different donor and acceptor compounds and to commensurate and incommensurate intercalants. A deviation from the theoretical stoichiometry is measured for most of the compounds using this non-destructive method. Within experimental error, the RBS results agree with those obtained from analysis of the (00ℓ) x-ray diffractograms and weight uptake measurements on the same samples.

On the defects of enamel coatings

2019 ◽  
pp. 145-150
Author(s):  
T. O. Soshina ◽  
V. R. Mukhamadyarovа
Keyword(s):  
Heat Treatment ◽  
Surface Tension ◽  
Electron Microscope ◽  
Enamel Coating ◽  
Surface Defects ◽  
Linear Expansion ◽  
Corrosion Properties ◽  
Treatment Conditions ◽  
Mechanical And Corrosion Properties ◽  
Coefficient Of Linear Expansion

The defects destroy the integrity of the enamel, and the paper examines the influence of the physical-mechanical and corrosion properties of frits and heat treatment on the defectiveness of the enamel coating. The surface defects were scanned by electron microscope. It has been established that the defectiveness of enamel coatings depends on the melting index, temperature coefficient of linear expansion, surface tension of the frits, and heat treatment conditions. When burning rate of the enamel coating decreases, the fine-meshed structure of the enamel changes, and the size of the defects decreases.

scholarly journals Manufacturing PLA/PCL Blends by Ultrasonic Molding Technology

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2412
Author(s):  
Inés Ferrer ◽  
Ariadna Manresa ◽  
José Alberto Méndez ◽  
Marc Delgado-Aguilar ◽  
Maria Luisa Garcia-Romeu
Keyword(s):  
Molecular Weight ◽  
Crystallization Rate ◽  
Raw Material ◽  
Small Particle Size ◽  
Polymer Mixtures ◽  
Crystallinity Degree ◽  
Correct Determination ◽  
Production Stages ◽  
Process Speed

Ultrasonic molding (USM) is a good candidate for studying the plasticization of polymer mixtures or other composite materials due to either the little amount of material needed for processing, low waste or the needed low pressure and residence time of the mold. Thus, the novelty of this research is the capability of USM technology to process PLA/PCL blends and their corresponding neat materials, encompassing all the production stages, from raw material to the final specimen. The major findings of the work revealed that the thermal properties of the blends were not affected by the USM process, although the crystallinity degree experienced variations, decreasing for PLA and increasing for PCL, which was attributed to the crystallization rate of each polymer, the high process speed, the short cooling time and the small particle size. The employed ultrasonic energy increased the molecular weight with low variations through the specimen. However, the degradation results aligned with the expected trend of these material blends. Moreover, this study also showed the effect pellet shape and dimensions have over the process parameters, as well as the effect of the blend composition. It can be concluded that USM is a technology suitable to successfully process PLA/PCL blends with the correct determination of process parameter windows.

Sign in / Sign up

Export Citation Format

Share Document