Butyl Rubber typically contains about 98% polyisobutylene with 2% isoprene distributed randomly in the polymer chain. To achieve high molecular weight, the reaction must be controlled at low temperatures (-90 to -100 degC).The reaction is highly exothermic.utyl Rubber typically contains about 98% polyisobutylene with 2% isoprene distributed randomly in the polymer chain. To achieve high molecular weight, the reaction must be controlled at low temperatures (-90 to -100 degC).
There may be no single cause of bipolar disorder (aka manic depression). Instead, research indicates the causes of bipolar disorder are probably a combination of biochemical, genetic and environmental factors that may trigger and perpetuate the chemical imbalances in the brain.
Another factor that may lead to bipolar disorder is the brain structure or the brain function of the person with the disorder. Scientists are finding out more about the disorder by studying it. This research may help doctors do a better job of treating people.