Understand the rubber products method to detect the performance test and high temperature vulcanization
High temperature vulcanization processing is important in the manufacturing process of rubber and silicone products, the process of rubber and silicone has a certain gap, normal vulcanization silicone manufacturer to add complementary material and vulcanizing temperature performance is different, and rubber products processing sulfide is different it is changed from linear to make rubber macromolecule chain mesh crosslinking process, so as to obtain good physical and mechanical properties and chemical properties.
Rubber vulcanization performance is in rubber vulcanization process of various performance indicators or phenomenon, to scientific research, the direct production of great practical value, vulcanization properties including coke burning performance, are vulcanization time and vulcanization process, such as determination of rubber vulcanization performance method are many.
Best with rheometer and bubble point analyzer.
(1) Mooney viscosity meter practice, viscosity meter method can not only determine raw rubber Mooney viscosity and mixing rubber Mooney viscosity, the characterization of the rheological properties of the rubber, and can determine the thixotropic effect of rubber, elastic recovery, charred characteristics and sulphur index, such as performance, so it is the earliest tool for determination of rubber vulcanization curve.
Though Mooney viscosity meter cannot direct reading is curing time, but it can be used to calculate the vulcanization time.
2 rheometer method rheometer is dedicated to test of rubber vulcanization characteristic test instrument, there are many types.
According to the principle has two kinds big.
The first category in rubber vulcanization exert a certain amplitude of force, to determine the corresponding deformation such as rheometer;
The second type is the general category.
This kind of rheometer in the rubber vulcanization exert a certain amplitude distortion, determine the corresponding shear stress, such as vibration disc type rheometer.
Rubber Mooney scorch test rubber scorch is rubber phenomenon of early sulfide in the process, each rubber formula has its scorch time (
Including operating scorch time and the rest of the scorch time)
In production should control the length of this period of time.
If too short, the coke burning occur in the operating process flow or vulcanized rubber is not fully, and make pattern is not clear and affect product quality or even waste, if scorch time is too long, cause the curing cycle growth, thus reducing the production efficiency.
Determination of the current widely used method is the Mooney scorch time scorch viscometer (
Determination of the scorch time is called the Mooney scorch time)
, also can use rheometer test of the rubber in the early time,
Mooney scorch the test principle of Mooney viscosity meter is used to test rubber scorch is under specific conditions, according to the unvulcanized rubber Mooney viscosity changes, determination of rubber vulcanization phenomenon began to appear.
Determination of rubber vulcanization characteristics for rubber vulcanization process of rubber vulcanization degree and the used methods include chemical method (
In combination with sulphur, swelling)
Physical and mechanical properties, method (
Constant stress method, the tensile strength, permanent deformation, etc. )
, the main drawback of these methods can't be the outline of the continuous determination of curing process.
Rheometer solved the problem, and the method of the determination of degree of cure one step further.
Rheometer is developed in the 1960 s a good rubber testing instruments.
Widely applied to the determination of rubber vulcanization characteristics.
Rheometer can continuously and visually describe the curve of the whole process of vulcanization, thereby gaining some main parameters in the process of rubber vulcanization.