Properties annealing effect

The present review shows how the microhardness technique can be used to elucidate the dependence of a variety of local deformational processes upon polymer texture and morphology. Microhardness is a rather elusive quantity, that is really a combination of other mechanical properties. It is most suitably defined in terms of the pyramid indentation test. Hardness is primarily taken as a measure of the irreversible deformation mechanisms which characterize a polymeric material, though it also involves elastic and time dependent effects which depend on microstructural details. In isotropic lamellar polymers a hardness depression from ideal values, due to the finite crystal thickness, occurs. The interlamellar non-crystalline layer introduces an additional weak component which contributes further to a lowering of the hardness value. Annealing effects and chemical etching are shown to produce, on the contrary, a significant hardening of the material. The prevalent mechanisms for plastic deformation are proposed. Anisotropy behaviour for several oriented materials is critically discussed. 

The design of light sensitive polymeric amphiphiles is discussed and their aggregation behaviour and the properties of LB—multilayers made from them are investigated. Enhanced thermal stability and annealing effects were found. In addition the photoreaction of amphiphilic Benzylammoniumsalts in Liposomes and LB—multilayers and its influence on the structure of these supramolecular systems was investigated. 

PVC MeOH, CHX, Toluene, THF, Decane, CS The slowest evaporating solvent has the greatest effect on the surface properties annealing above Tg reduces the surface porosity. Inverse Gas Chromatography, DSC [Wildman and Hsu, 1984]... 

The unexpected transition in the electrical conductivity was attributed to the interactions between the MWCNTs and the CPs inside the fiber due to an annealing effect of the PANl/PEO matrix from the thermal dissipation of the carbon nanotubes (CNTs). It was also related to the self-heating effect of the MWCNTs incorporated into the CPs, which will be very helpful in enhancing the electrical properties of nanoscale conducting composite fibers. 

Tsuji H., Ikada Y., Properties and morphologies of poly(L-lactide) 1. Annealing effects on properties and morphologies of poly(L-lactide), Polymer, 36, 1995, 2709-2716. 

S. Kim, I. J. Chung, Annealing effect on the electrochemical property of polyaniline complexed with various acids, Synthetic Metals 1998, 97, 127. 

SantoveaA, Piero MJ, Uabres M (2010) Comparison between DSC tmd TMDSC in the investigation into frozen aqueous cryoprotectants solutions. Drag Dev Ind Pharm 36 1413-1421 Saxena A, Jean YC, Suryanarayanan R (2013) Annealing effect reversal by water sorption-desorption and heating above the glass transition temperature—comparison of properties. Mol Pharm 10 3005-3012... 

Z. Beji, L. Smiri, N. Yaacoub, J.M. Greneche, N. Menguy, S. Ammar, F. Fievet, Annealing effect on the magnetic properties of Polyol-made Ni-Zn Ferrite nanoparticles. Chem. Mater. 22, 1350-1366 (2010)... 

Alam M.J., Cameron D.C. Optical and electrical properties of transparent conductive ITO thin films deposited by sol-gel process. Thin Solid Films 2000 00 455 59 Alam M.J., Cameron D.C. Investigation of annealing effects on sol-gel deposited indium thin oxide thin films in different atmospheres. Thin Solid Films 2002 420-421 76-82 Anderson H.U., Pennell M.J., Guha J.P. Polymeric synthesis of lead magnesium niobate powders. Adv. Ceram. 1987 21 91-98... 

For higher extrusion temperatures, the annealing effect is favoured and molecular relaxation and recrystallisation are more likely to occur. Because of the variation in crystallinity with increasing draw ratio, tensile strength and modulus significantly increase as a fibrillar structure is formed starting from the spherulitic material. An increase of these properties with molecular weight also... 

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