Glass transition temperatures of a very wide molecular-weight range of ethylene oxide polymers were measured by mechanical loss and by broadline NMR. Starting at about -95°C for ethylene glycol, the glass transition rises to a maximum of -17° for molecular weight 6000 and then drops off to -53° for polymers with molecular weights greater than 200 000. This unusual behavior is probably caused by the high crystallinity of the intermediate molecular-weight polymers.

In ethylene copolymers isolatedCH2CHRCH2 groups undergo a glass transition at about −10 to −50°C., the exact temperature depending upon the nature of R. For any given copolymer the temperature of the transition remains reasonably constant over a broad composition range at high ethylene contents. At high comonomer content the transition rises with composition along the line drawn between the glasstransition temperature of polyethylene and that of the homopolymer of the comonomer in question. A second glass transition is also observed in ethylene copolymers at about −125°C. over the whole composition range. This transition corresponds to motion of CH2 sequences of three to five or more in the main chain. The temperature position of this transition is usually independent of the nature of the rest of the chain. The behavior of ethylene copolymers is quite different from that of normal vinyl copolymers, where only a single glass transition is observed for each composition and where the temperature position of the transition changes uniformly with composition along the line drawn between the glass transitions of the respective homopolymers. It is concluded that the motions involved in the glass transitions of the main chain CH2 sequences and of isolated CH2CHRCH2 groups in ethylene copolymers are localized, involving only a few carbon atoms. In the case of the normal vinyl copolymers, on the other hand, the motion at the transition appears to be a long‐range motion involving a great many chain carbon atoms and cooperative motion of the pendent groups. This change in the nature of the motion involved at the glass transition in going from high ethylene content copolymers to low ethylene content or vinyl copolymers appears to arise because of steric hindrance and/or restrictive dipolar forces between the pendent groups of the CH2CHRCH2 segments in those cases were they are not isolated from each other. Finally, it is concluded that all vinyl homopolymers would have glass transitions in the −10 to −50°C. range if steric hindrance between the side groups did not occur. It is shown that as the pendent group becomes less bulky or is further separated from the main chain by CH2groups the glass transition temperature decreases presumably towards the −10 to −50° range characteristic of the transition of isolated CH2CHRCH2 groups.

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Sorption of Polymer JR, a cationic cellulose ether, by human hair is greatly decreased in the presence of added electrolytes. This reflects the competition between cations of the added salt and the quaternary ammonium groups of the polymer for sorption sites in the substrate. In this respect the hair can be regarded as a “strong-acid” ion-exchanger, and it displays a selectivity to ions similar to that observed for conventional resin exchangers. Cations can be ranked in order according to their ability to decrease the sorption of Polymer JR as follows: La+++ > Al+++ < Fe+++ < Ca++ < Fe++ < Cs+ < Na+ < Li+. Salts also promote desorption of Polymer JR that is already sorbed by hair. However, selectivity is less evident in desorption than in sorption and is only observed at relatively low concentrations of salt. About half of the sorbed polymer is readily removed by salt solutions; the rest appears to be tightly attached to the substrate.