Annealing leads to a better fit of the hydrogen bonded macromolecules and a significant increase in degree of crystallinity
and crystal perfectioning is achieved .
For processors, the copolymer grades are attractive because of the lower process temperature associated with lower crystallinity
and also a wider process window.
Based on DSC (differential scanning calorimeter) characterization, performed on a Q100 DSC from TA instruments, PHO has a melting peak at 63[degrees]C, crystallinity
of 15%,1 and a Tg at -38[degrees]C (first heating scan); there is no melting transition during the second scan.
The ratio of the crystalline area to that of the total diffracted area was used to determine the relative crystallinity
XRD was also used to measure the degree of crystallinity
of the NCC according to the following equation:
Various vibrational spectroscopic techniques, such as near-infrared (NIR), have also been proposed for estimating polymer crystallinity
since they are rapid and non-intrusive, they require little or no sample preparation, and provide a wealth of information (Lachenal, 1995).
This combination of internal standards were chosen because (a) SRM 676 is the 'standard' internal standard and is being certified for crystallinity
, (b) the rutile internal standards have an absorption coefficient between that of the highest (magnetite) and lowest (quartz) absorbing materials in the samples and (c) different particle sizes may yield information of particle size effects on microabsorption.
Values in the risedronate group after 5 years of treatment were also virtually unchanged from baseline: The mean crystallinity
ratio was 0.
This section includes: density, molecular weight and molecular weight distribution, crystallinity
, thermal properties, mechanical properties, electrical properties, optical properties, surface properties, hardness and scratch resistance, abrasion resistance, friction, acoustic properties, degradation, biological behaviour, biocompatibility, wear, molecular properties, performance in service, permeability, and crosslinking.
The degradation behavior of PLA depends largely on the molecular weight, crystallinity
, geometry, and surrounding environment (temperature, moisture, pH, presence of micro-organisms, etc.
Deformation under creep conditions, as well as increasing with time, load (stress) and temperature, is reduced by increasing the level of crystallinity
, by the addition of fillers and by introducing crosslinking.
They have an x-ray crystallinity
of 40 to 80% and do not requiring poling.