We report a novel method of detecting the glass --> liquid transition at high pressures, which comprises measuring the relative volume change incurred upon heating glassy samples into the liquid state. We show data on glycerol in the pressure range 0.050-1.00 GPa to demonstrate the viability of the method. The reversible glass --> liquid transition is observed by means of a kink in the relative...

In differential scanning calorimetry (DSC), remnant moisture loss in samples often overlaps and distorts thermal events such as glass transitions. Temperature modulated DSC (TMDSC) is known for separating such overlapping processes. In this study, chitosan was depolymerized by oxidative degradation method. By this method, chitooligomers of different molecular weights were produced. The glass tr...

The dependence of the glass transition temperature on silicate composition as well as on borate composition is discussed. Some new experimental results on borosilicate glass-enamels are put together with the existing literature data. It is demonstrated that in the glass transition interval the activation energy E(Tg) for viscous flow is related to the glass transition temperature. The activatio...

crosslinked poly(acrylic acid)s were prepared using two types of crosslinker by precipitation polymerization method in a binary organic solvent. n,n’-methylenebisacrylamide (mba) and polyethylene glycol dimethacrylate (pegdma-330) were used as low-molecular weight and long-chain crosslinkers, respectively. the effect of various types of crosslinkers on polymer characteristics (i.e., gel content...

Polymer-nanoparticle composites play a vital role in ongoing materials development. The behavior of the glass transition of these materials is important for their processing and applications, and also represents a problem of fundamental physical interest. Changes of the polymer glass transition temperature Tg due to nanoparticles have been fairly well catalogued, but the breadth of the transiti...

Extensive studies on polymer thin films to date have revealed their interesting but unusual properties such as film thickness dependence of glass transition temperature Tg and thermal expansivity. Recent studies have shown that the lower Tg is not always related to the higher mobility in polymer thin films, which contradicts our current understanding of the glass transition process. In this wor...

When a liquid is cooled below its melting temperature, it usually crystallizes. However, if the quenching rate is fast enough, the system may remain in a disordered state, progressively losing its fluidity upon further cooling. When the time needed for the rearrangement of the local atomic structure reaches approximately 100 seconds, the system becomes "solid" for any practical purpose, and thi...

New Fe-based bulk glassy alloys were synthesized in the (Fe0.75B0.15Si0.10)100−x Nbx system by copper mould casting. The maximum diameter of the bulk glassy alloy rod was 0.5 mm at 1 at%Nb, 1.0 mm at 2 at%Nb and 1.5 mm at 4 at%Nb. No glass transition is observed at 0 at%Nb, but the addition of Nb causes the appearance of glass transition before crystallization. The glass transition temperature ...

4-chloromethyl styrene (cms) was copolymerized with different monomers such as methyl methacrylate (mma), methyl acrylate (ma), 2-ethylhexyl acrylate (eha) by free radical polymerization method at 70 ±1°c using a,a'-azobis(isobutyronitrile) (aibn) as an initiator. the copolymer compositions were obtained using related 1hnmr spectra and the polydispersity of the copolymers were determined using ...