Dark Stool: If your stool is black or bright red in color, it can mean that you are bleeding internally, as a possible result of an ulcer or cancer, and warrants a call to your doctor even if you think it could be hemorrhoids, or tiny tears in the anal tissue, due to constipation and straining.
The chemical reaction in which high molecular mass molecules are formed from monomers is known as polymerization. There are two basic types of polymerization, chain-reaction (or addition) and step-reaction (or condensation) polymerization.
Rubber, Natural. caoutchouc, crude rubber, a polymer of plant origin, the vulcanization of which produces processed rubber. Natural rubber is one of the elastomers, a group of macromolecular compounds that possess the capacity for considerable reversible deformation at room temperatures and lower.