A model study on effect of glucose on the basic characteristics and physical properties of natural rubber

2013 ◽  
Vol 32 (8) ◽  
pp. 1408-1416 ◽  
Author(s):  
Adun Nimpaiboon ◽  
Jitladda Sakdapipanich
1941 ◽  
Vol 14 (3) ◽  
pp. 580-589 ◽  
Author(s):  
G. Gee ◽  
L. R. G. Treloar

Abstract As high elasticity is a property possessed only by substances of high molecular weight, it is of interest to enquire into the relation between the elastic properties of a highly elastic material such as rubber and its molecular weight. An investigation on these lines has been made possible through the work of Bloomfield and Farmer, who have succeeded in separating natural rubber into fractions having different average molecular weights. The more important physical properties of these fractions have been examined with the object of determining which of the properties are dependent on molecular weight and which are not. Fairly extensive observations were made on the fractions from latex rubber referred to as Nos. 2, 3 and 4 by Bloomfield and Farmer, and some less extensive observations were carried out on the less oxygenated portion of fraction No. 1 obtained from crepe rubber (called hereafter 1b) . Before considering these experimental results, and their relation to the molecular weights of the fractions, it will be necessary to refer briefly to the methods used for the molecular-weight determinations, and to discuss the significance of the figures obtained.


1935 ◽  
Vol 8 (4) ◽  
pp. 641-654
Author(s):  
S. L. Brous ◽  
W. L. Semon

Abstract Rubber has found its widest use in industry because its properties can be altered and improved by compounding and cure to give strong, flexible, resilient products which are resistant to abrasion, impervious to fluids, electrically insulating, and relatively inert chemically. For such other desirable characteristics as resistance to oils and solvents, and freedom from attack by air, sunlight, and oxidizing materials, skillful compounding has brought marked improvements, but even better properties are needed to meet the demands of modern industry. The search for synthetic rubbers has been stimulated not merely by the desire for an economically independent source of supply, but also with the hope that there might be obtained materials having properties superior to the natural product. Whitby and Katz (4) have published a comprehensive historical treatise dealing with the development of numerous synthetic rubbers which have appeared in the last few years. It has been believed that linear polymers obtained from dienes hold most promise for the preparation of rubber-like materials. Carothers (1) has studied the relation between the structure of dienes and the types of polymerization products which may be obtained therefrom. On the basis of these data he inferred that, from the standpoint of their polymerization products, the best dienes will be of the type CH2:CXCH:CH2, in which X is an activating group other than alkyl or aryl. In general it has been found that there may be obtained polymerization products with physical properties equal to, or often superior to those of natural rubber, and with marked resistance to the action of solvents and chemicals. Among the many types of organic materials which will polymerize, the vinyl compounds only recently have been modified suitably to yield commercial rubber-like materials.


2012 ◽  
Vol 19 (7) ◽  
Author(s):  
Chalermpan Keawkumay ◽  
Kasama Jarukumjorn ◽  
Jatuporn Wittayakun ◽  
Nitinat Suppakarn

2012 ◽  
Vol 69 (6) ◽  
pp. 635-647 ◽  
Author(s):  
Sa-Ad Riyajan ◽  
Isara Intharit ◽  
Pramuan Tangboriboonrat

2000 ◽  
Vol 73 (5) ◽  
pp. 902-911 ◽  
Author(s):  
Amit K. Naskar ◽  
S. K. De ◽  
A. K. Bhowmick ◽  
P. K. Pramanik ◽  
R. Mukhopadhyay

Abstract Ground rubber tire (GRT) particles of different sizes were characterized and the effect of these particles in a natural rubber (NR) compound was studied. It is found that smaller particles contain less polymer, but have higher amounts of fillers and metals with respect to polymer. NR compound containing smaller GRT particles shows better physical properties, but poorer aging characteristics.


1969 ◽  
Vol 42 (3) ◽  
pp. 924-935 ◽  
Author(s):  
T. Colclough ◽  
J. I. Cunneen ◽  
G. M. C. Hrggins

Abstract A natural rubber vulcanizate containing almost entirely monosulfidic crosslinks was oxidized in oxygen and with tert-butyl hydroperoxide. The changes in physical properties due to oxidation were followed by stress—strain measurements, and the changes in chemical structure were investigated with chemical probes, and by spectroscopic methods. The results show that when the oxidized vulcanizates are heated at 75° C, the monosulfidic crosslinks are broken, that crosslinks containing two sulfur atoms are formed, and that conjugated diene and triene structures are introduced into the main polyisoprene chains.


Author(s):  
Porntip Rojruthai ◽  
Narueporn Payungwong ◽  
Jitladda T Sakdapipanich

A model study on the influence of some heavy metal ions on the stability and vulcanization efficiency of uncompounded and compounded high-ammonia natural rubber (HANR) latex was carried out by an exogenous addition and then determined by Brookfield viscometer, mechanical stability time (MST) tester, and tensile testing machine. The case of pre-vulcanized HANR latex with different aging times was determined by the change in the volatile fatty acid (VFA) number, MST, and viscosity. The compounded HANR latex was coagulated by adding Mn2+and Mg2+ while it was unaltered by adding Zn2+, Fe2+, and Cu2+ ions, leading to their colloidal stability. Therefore, these metal ions were chosen further to study the pre-vulcanization of compounded HANR latex. The presence of Zn2+, Fe2+, and Cu2+ in the latex is responsible for the delay in the vulcanization process and changes the appearance of compounded latex. Before compounding, the addition of such metal ions led to the reduction in tensile strength of the obtained gloves. At the same time, there was no effect on the tensile properties of the gloves made from the compounded HANR latex containing the metal ions.


2020 ◽  
Vol 26 (4) ◽  
pp. 423-433
Author(s):  
Karnjana Sawangpet ◽  
Alif Walong ◽  
Bencha Thongnuanchan ◽  
Azizon Kaesaman ◽  
Tadamoto Sakai ◽  
...  

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