Molecular weights of backbones in graft copolymers

✍ Scribed by R. Collins; M.B. Huglin; R.W. Richards

• Book ID: 103074529
• Publisher: Elsevier Science
• Year: 1975
• Tongue: English
• Weight: 541 KB
• Volume: 11
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(75)90062-2

✦ Synopsis

Abslract--Copolymerization of a monomer X with an existing polymer yields a copolymer contaminated by poly-X homopolymer and ungrafted polymer. Measurements on the pure copolymer can yield only the molecular weights of the cumulative backbone portion and of the cumulative graft portion. However, if the grafts can be isolated, then the molecular weights of their individual chains may be determined also. Since it is not isolatable, the backbone is not amenable to similar treatment. Equations are derived for the molecular weights {of any average) of individual backbone chains; they are expressed in terms of the following experimentally, accessible quantities: (i) molecular weight of original polymer; (ii) molecular weight of ungrafted portion: and fiiil fraction by weight of the original polymer which remains ungrafled The procedure is thus the analogue, applied to the backbone, of chemical isolation applied to the grafts. The treatment has been examined for copolymers prepared b3 grafting acrylic acid to nylon-6 by mutual irradiation.