Dense suspensions of multiarm star polymers are known to develop liquidlike microstructure, which has been attributed to the similarities between high functionality stars and colloidal particles interacting via soft, long ranged potentials. Recent experimental studies reported a counterintuitive solidification of suspensions with f=128 , upon increase of the temperature in marginal solvents. We...

Understanding why the glass transition temperature (Tg) of polymers deviates substantially for the bulk with nanoscale confinement has been a 20-year mystery. Ever since the observation in the mid-1990s that the Tg values of amorphous polymer thin films are different from their bulk values, efforts to understand this behavior have intensified, and the topic remains the subject of intense resear...

During desorption of penetrant-saturated polymers, a glassy skin can form at the exposed surface. The associated dynamics are not purely Fickian due to viscoelastic relaxation effects in the polymer. A model is presented which captures these nonlocal effects. The motion of the glass-rubber interface and the accumulated desorbed flux are calculated. The model also describes trapping skinning, wh...

A series of lactic/glycolic acid polymers with various molar ratios of lactic to glycolic acid and various molecular weights were synthesized using the ring-opening polymerization method. The polymerization conditions for the lactic/glycolic acid polymer synthesis were as follows: 150 degrees C, 700 microm Hg, 3 h, 0.03 wt% of catalyst (stannous 2-ethyl-hexanoate) concentration. The molecular w...

Cyanoacrylates were commercially introduced in 1950 by Tennesee Eastman Company. Cyanoacrylate adhesives are monomeric adhesives. They are generally quick-setting materials which cure to clear, hard glassy resins, useful as sealants, coatings, and particularly adhesives for bonding together a variety of substrates [1]. Polymers of alkyl 2-cyanoacrylates are also known as superglues. In addition...