N-(2-Methyl-2-nitropropyl) and N-Nitroso Derivatives of Some Diamines

1995 ◽  
Vol 60 (9) ◽  
pp. 1541-1550 ◽  
Author(s):  
Stanislav Kafka ◽  
Antonín Klásek ◽  
Petr Sedmera
Keyword(s):  
Dynamic Properties ◽  
Vulcanized Rubber ◽  
Derivatives Of

Preparation of ten new derivatives of 1,6-hexanediamine and 1,4-bis(4-aminophenoxy)butane with different combination of N-nitroso and/or N-(2-methyl-2-nitropropyl) groups is presented. The title compounds are potential improvers of vulcanized rubber dynamic properties.

Nonlinearity in the Dynamic Properties of Vulcanized Rubber Compounds

1954 ◽  
Vol 27 (1) ◽  
pp. 209-222 ◽  
Author(s):  
W. P. Fletcher ◽  
A. N. Gent
Keyword(s):  
Simple Shear ◽  
Dynamic Modulus ◽  
Dynamic Properties ◽  
Mechanical Vibration ◽  
Frequency Range ◽  
Vulcanized Rubber ◽  
Rubber Compounds ◽  
Chemical Combination ◽  
Wide Range ◽  
Static Shear

Abstract Measurements are described of the dynamic properties of rubber, loaded with various amounts and types of filler, when subjected to mechanical vibration in simple shear at amplitudes from 0 to 3 per cent shear in the frequency range 20 to 120 c.p.s. The decrease of dynamic modulus with increasing amplitude is shown, for a wide range of filler types and concentrations, to be determined by the amount of stiffening produced by the filler. This relationship is not influenced by variations in the vulcanizing ingredients, reasonable variations in state of vulcanization, addition of softener, or imposition of static shear strain. Rubber compounds stiffened by mixture with, or chemical combination of, other polymers exhibit a smaller order of nonlinearity than that described above and also exhibit much lower hysteresis values within the amplitude range 0 to 3 per cent shear.

A Study of the Rubber-Metal Bond

1946 ◽  
Vol 19 (4) ◽  
pp. 956-967
Author(s):  
S. Buchan ◽  
J. R. Shanks
Keyword(s):  
Tensile Strength ◽  
Low Temperature ◽  
Low Temperatures ◽  
Moderate Increase ◽  
Progressive Reduction ◽  
Bonding Agents ◽  
Metal Bond ◽  
Permanent Set ◽  
Vulcanized Rubber ◽  
Derivatives Of

Abstract Although the practice of bonding rubber to metal has been in use for many years, no theories appear to have been advanced which explain adequately the mechanism of bonding. It has been stated that the brass bond between rubber and metal functions through chemical linkages, but this can only be regarded as tentative and has yet to be proved. No attempt has been made to find out how ebonite functions as a bonding medium or the more recently discovered derivatives of rubber, such as sulfonated rubber, chlorinated rubber, and rubber hydrohalides. Until it is properly elucidated just how bonding agents do act, further logical development of improved bonding media cannot be pursued. It is intended in this paper to show how the rubber-metal bond behaves at subnormal temperatures and how a low temperature technique may be used for studying the mechanism of bonding. The effect of low temperatures on the tensile strength and associated properties of vulcanized rubber, such as hardness, permanent set, flexibility, resilience and flexing, has been dealt with fairly comprehensively in the literature. Progressive reduction in temperature leads to only a moderate increase, for example, in tensile strength, until the point is reached at which the rubber stiffens and freezes, when a marked increase occurs. Examination of a brass-bonded unit at low temperatures revealed that the graph obtained for bond strength was very similar in slope and character to that for tensile strength. The similarity is illustrated by the data in Table 1 and in Figure 1.

Effect of Primary Molecular Weight on the Dynamic Properties of Cured Rubber

1959 ◽  
Vol 32 (3) ◽  
pp. 651-661
Author(s):  
E. V. Kuvshinskiĭ ◽  
M. M. Fomicheva
Keyword(s):  
Molecular Weight ◽  
Dynamic Modulus ◽  
Room Temperature ◽  
Dynamic Properties ◽  
Molecular Weights ◽  
Vulcanized Rubber ◽  
Equilibrium Modulus ◽  
Modulus Of Resilience ◽  
Molecular Weight Fractions ◽  
Butadiene Styrene

Abstract 1. Studied were the moduli of resilience and rebound elasticity of the vulcanized rubbers made from fractions of butadiene-styrene rubber “SKS-30-A” at temperatures of 20, 60, and 100° C in the region of molecular weights from 45,000 to 620,000 with various degrees of vulcanization (with variation in the pseudoequilibrium modulus from 5 to 70 kg/cm2). 2. The dynamic modulus of resilience is little dependent on the molecular weight of the original rubber both at room temperature and at higher temperatures. 3. At higher temperatures the elasticity of vulcanized rubber is mainly determined by the degree of vulcanization, the measure of which is the pseudo-equilibrium modulus, and is little dependent on the initial molecular weight. At low temperatures (20° C) elasticity increases with the degree of vulcanization, but it increases at different rates for vulcanized rubbers made from fractions with different molecular weights. At 20° C the increase in the degree of vulcanization increases the elasticity of vulcanized rubbers made from low-molecular fractions (45,000) to a lower degree than of those made from high molecular weight fractions (above 133,000). 4. The value of the maximum elasticity of vulcanized rubbers obtained from rubbers of the same molecular weight is not dependent on the type of accelerator used.

scholarly journals Mathematical models of the pneumatic cascade and a mem-brane pneumatic actuator described by the fractional calculus

2018 ◽  
Vol 19 (12) ◽  
pp. 526-531
Author(s):  
Mirosław Luft ◽  
Artur Nowocień ◽  
Daniel Pietruszczak
Keyword(s):  
Differential Equation ◽  
Differential Equations ◽  
Fractional Calculus ◽  
Dynamic Systems ◽  
Dynamic Properties ◽  
Pneumatic Actuator ◽  
Programming Tool ◽  
Analysis And Synthesis ◽  
Continuous Dynamic ◽  
Derivatives Of

The paper presents the analysis of dynamic properties of pneumatic systems such aa pneumatic cascade and a membrane pneumatic actuator using differential equations of integer orders and differential equations with derivatives of non-integer orders. The analyzed systems were described in the domain of time by means of step characteristics and in terms of frequency with the help of Bode characteristics, i.e. logarithmic amplitude and phase characteristics. Each characteristic was determined on the basis of a differential equation with derivatives of non-integer order. To determine the characteristics, an irreplaceable programming tool was the interactive Simulink package built on the basis of the MATLAB programme, which allows the analysis and synthesis of continuous dynamic systems.

The Proöxygenic Effect. Changes Which Take Place in Vulcanized Rubber

1945 ◽  
Vol 18 (3) ◽  
pp. 607-609 ◽  
Author(s):  
Paul Chovin
Keyword(s):  
Chloroform Solution ◽  
Average Content ◽  
Iron Cobalt ◽  
Complex Metal ◽  
Rubber Sample ◽  
Vulcanized Rubber ◽  
Copper Acetylacetonate ◽  
Metal Derivatives ◽  
Derivatives Of ◽  
Determinant Factor

Abstract The autoöxidation of rubber is sensitive to the action of catalysis; anti-oxygenic compounds are antagonistic to the process and retard its progress; proöxygenic compounds on the contrary promote autoöxidation, and in their presence the effects of autoöxidation are evident sooner. In the present paper, experiments are described, the object of which was to study the action of a few typical proöxygenic compounds on rubber hydrocarbon. Among the substances which accelerate the action of oxygen, certain salts of copper, iron, cobalt, and manganese are known to be very active. Various organic derivatives of these metals were studied in the present work, including (1) copper acetylacetonate, oleate, linoleate, sulforicinoleate, elaidate, stearate, enanthate, pelargonate, hendecenate, erucate, and diethylthioneethiolcarbamate; (2) iron acetylacetonate, oleate, linoleate, sulforicinoleate, and pelargonate, and the dibenzoylmethane derivative of iron; (3) cobaltous oleate, linoleate and sulforicinoleate, and cobaltic acetylacetonate; (4) manganous oleate, linoleate, sulforicinoleate and pelargonate, and manganic acetylacetonate. A study was also made of certain more complex metal derivatives, including salts of the dithizone of cupferron, of mercaptobenzothiazole, of α-nitrose-β-naphthol, of benzyldioxime, etc. The method followed involved two steps: (1) incorporation of a predetermined percentage of a proöxygenic metal compound into samples of vulcanized rubber, (2) estimation of the acceleration of autoöxidation induced by the particular proöxygenic compound. In the first step, the rubber sample was cut into small cubical pieces 2–3 mm. on a side, and these were placed in a chloroform solution of the particular salt under investigation. The average content of proöxygenic compound which was absorbed was about 0.1 per cent. The swelling of the rubber in the solution was the determinant factor in the total amount of proöxygenic compound and solvent which were absorbed.

The Dynamic Properties of Carbon Black-Loaded Natural Rubber Vulcanizates. Part I

1963 ◽  
Vol 36 (2) ◽  
pp. 432-443 ◽  
Author(s):  
A. R. Payne
Keyword(s):  
Thermal Treatment ◽  
Carbon Black ◽  
Natural Rubber ◽  
Dynamic Modulus ◽  
Dynamic Properties ◽  
Viscosity Change ◽  
Vulcanized Rubber ◽  
Elastic Responses ◽  
Natural Rubber Vulcanizates

Abstract The dynamic properties of a natural vulcanized rubber containing carbon black were studied for dynamic tensions of amplitude varying greatly. It was shown that both the elastic responses and viscosity change with amplitude of oscillation and with concentration and type of carbon black. The effects of thermal treatment on the dynamic modulus were also studied. Beginning with conditions of equilibrium between the hard and soft regions of the vulcanizate for very weak stresses, the values for the formation of hard regions from soft regions were determined by means of the Van't Hoff isochore.

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