DEGREE AND RATE OF CROSSLINKING OF CROSS LINKED POLYETHYLENE,
Abstract
Chemically crosslinked polyethylene has unique characteristics among crosslinked polymers used industrially. First, the number average molecular weight before crosslinking is very small; second, an appreciable amount of sol is contained in its crosslinked state. In order to obtain precise values of the crosslinkage density in such a material, it is necessary to develop a new technique. A new equation developed is proposed in this paper. It is based on the Flory-Rehner equation, but the number average molecular weight of the polymer prior to crosslinking is modified in terms of sol fraction. Another correction is made considering the distribution of crosslinkages between sol and gel. The new equation was proved to give reliable values over a wide range of crosslinkage density. It has also been proved that the equation is not apt to be grossly affected by a minor experimental error. The rate of crosslinking of polyethylene with dicumyl peroxide is a first order reaction controlled by the rate of thermal decomposition of the peroxide, which is verified by measurements of swelling and sol using the new equation and by measurements with the Agfa Vulcameter. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1966
- Accession Number
- AD0646531
Entities
People
- Masaaki Okada