The enthalpy of melting of one HBPE sample increased from 79 to 90 and 94 J/g with and without the action of Lipomod 34P, respectively, in 7 days, showing the changes in the crystallinity of the polymer. The results prove that modified HBPEs are an important new class of biodegradable SB-715992 materials with a predictable degradation mechanism, and the degradation can be adjusted oil the basis of the molecular engineering. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 1873-1881, 2009″
“Various Ge-As-Se glasses spanning a mean coordination number (MCN) from 2.2 to 2.94 have been investigated using differential scanning calorimetry and Raman spectroscopy. The glass transition

temperature T-g was found to increase with increasing MCN, except for those glasses located within the nanoscale phase-separated region of the phase diagram. The evolution of Raman features at wavenumbers from 150 to 350 cm(-1) exhibits two transitionlike features. Merging of the 225 and 250 cm(-1) modes at MCN=2.5 is a

symbol of the extinction of Se-Se bonds. find more Additionally, the appearance of two modes at 280-290 and 170 cm(-1) at MCN > 2.7 come from the defect modes of ethanelike Ge2Se6/2. The increase in the scattering from these defects is an important factor leading to enhanced optical loss in the glasses with high MCN. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3204951]“
“With the growing emphasis on decreasing the accumulation of the used tyres in land fills, there has been significant scientific and technological interest to provide

with solutions to their recovery and reuse. A new composite material based on reused tyre powder as reinforcement and recycled high-density polyethylene as matrix was studied in this work. The effect of chemical acidic pretreatments performed on the rubber and of the particle BV-6 purchase size on the behavior of the composite material were evaluated. Powder of reused tyres resulting from industrial grinding processes was separated by sieving in three particle size categories: below 200 mu m, between 200-500 mu m and over 500 mu m. Pretreatments using H(2)SO4, HNO(3) , or a 50%, mix of H(2)SO(4) and HNO(3) were carried Out over the rubber before composite preparation. Mechanical tensile properties were evaluated to determine the effect of particle size and acid pretreatments on composite properties. Fracture surfaces of composite samples were also evaluated by scanning electron microscopy. Overall, all pretreatments improve the mechanical behavior of the obtained materials. This improvement is attributed to the development of a Surface of the rubber, more Suitable for mechanical adhesion. The effect of the particle size has a stronger influence in the properties of the material than the acidic pretreatments. (C) 2009 Wiley Periodicals, Inc.