The object of the experiment is to prepare rubber samples and measure their physical properties. By varying cure time, concentration of curing agent and filler content, rubbers of widely different stiffness can be obtained. The hardness and tensile properties of the samples are to be measured and related to the polymer structure.

Elastomers (rubbers) form an important class of materials and have uses ranging from large scale applications such as car tyres to specialty, high performance medical tubing. Elastomers are polymers which have been cross linked into a three dimensional network structure but in which the polymer strands are still mobile.

Vulcanization, the process of cross linking elastomers, occurs by a chemical process initiated through some form of energy input. It occurs between two statistically favorable reactive sites. In practical vulcanization, the most widely used group of elastomers consists of those containing a diene site for cross linking,

Fatty Acid: in this experiment stearic acid fills this role

It should be noted that the original unstrained length measurements of the filled samples were not recorded in order to use them in the calculations (see equation 2) they have been extrapolated from the printouts.

The mechanisms appear to proceed in the following steps:

Each of the samples (I, II, III, and IV) were then cut up and cured by placing them in a hydraulic press heated to 145„aC for varying lengths of time as given in Table 2

Some topics in this essay:
Ac-Sx-Ac Ac, Cross Sectional, Theory Elastomers, Sample Cure, Abstract Rubber, Zinc Oxide, IRHD Scale, Carbon Black, Stearic Acid, MBTS Note, natural rubber, cross linking, carbon black, plotted axis, table 3, sample cure, mm ¡Ã0005 mm, figure 1, curing agents, 1 2, ¡Ã0005 mm, slope resulting linear, relation irhd log, axis slope resulting, plotted axis slope,