Block & Bridle Annual 1959-1960

President Roger Wehrbein Vice President Ted Klug Secretary George B. O'Neal Treasurer Ralph Hazen Marshal Bud Reece Historian Tom Kraeger Co-Historian John Zauha Ag. Executive Representative Larry Williams Faculty Advisor Dr. E. B. Peo, Jr. George Ahlschwede Richard Hahn Henry Beel Ralph Hazen Gary Briggs Gary Heineman Leslie Cook Max Hauser Richard Eberspacher Buce Jameson Russ Edeal Leon Janovy William Ehresman Alan Jorgensen Rolland Eubanks John Joyner Mickey Evertson Marshall Jurgens Jesse Felker Ron Kahle Mylon Filkins Donald Kavan Richard Frahm Max Keasling Roger French Ronald Kennedy Angus Garey Ted Klug Ed Gates Herb Kraeger Gerald Gogan Tom Kraeger Gerald Goold Fernando Lagos Jay Graf Gerald Lamberson Lloyd Langemeier Ralph Langemeier Gerald Loseke Donald Meiergerd Lowell Minert John Oeltjen George B. O'Neal Don Ormesher Larry Ott Bud Reece Ron Sabatka Keith Smith Ronald Smith Donn Simonson Daryl Starr Galen Stevens Eugene Turdy Ernest Thayer Charles Thompson Jerry Thompson Eli Thomssen William Watkins Allen Trumble Robert Weber Lawrence Turner Dan Wehrbein Reginald Turner Roger Wehrbein Vance Uden Dick White Max Waldo Billy Williams Blair Williams Larry Williams D. Patrick Wright John Zauha

Association and Structure of Thermosensitive Comblike Block Copolymers in Aqueous Solutions

The structures and association properties of thermosensitive block copolymers of poly(methoxyoligo( ethylene glycol) norbornenyl esters) in D2O were investigated by small angle neutron scattering (SANS). Each block is a comblike polymer with a polynorbornene (PNB) backbone and oligo ethylene glycol (OEG) side chains (one side chain per NB repeat unit). The chemical formula of the block copolymer is (OEG3NB) 79- (OEG6.6NB) 67, where subscripts represent the degree of polymerization (DP) of OEG and NB in each block. The polymer concentration was fixed at 2.0 wt % and the structural changes were investigated over a temperature range between 25 and 68°C. It was found that at room temperature polymers associate to form micelles with a spherical core formed by the block (OEG3NB) 79 and corona formed by the block (OEG6.6NB) 67 and that the shape of the polymer in the corona could be described by the form factor of rigid cylinders. At elevated temperatures, the aggregation number increased and the micelles became more compact. At temperatures around the cloud point temperature (CPT) T ) 60 °C a correlation peak started to appear and became pronounced at 68 °C due to the formation of a partially ordered structure with a correlation length ∼349 Å.