Effects of drawing

Provide local air movement. Creating local air movement, even with warm air, provides a reduction in effective temperature and is inexpensive. A punkah type fan may be used, although this can have the effect of drawing down warmer air from a high level, or a portable fan in a box . It is advisable to have a multispeed fan to allow the effect to be adjusted by the operator for maximum comfort. 

EFFECT OF DRAWING SCHEMES ON TENSILE PROPERTIES OF MONOFILAMENT FIBERS... 

Perhaps, the most dramatic example of the effects of drawing on the spectra of a polymer comes from the stress-induced crystal transition of poly(butylene terephtha-late) 292,29 298 299). The phase transition of PTMT has been investigated above and below the glass transition temperature by means of dynamic infrared measurements... 

C for the bulk-crystallized sample, as shown in Fig. 12. A similar effect of drawing is also evident in the behavior of the narrow component, suggesting that the -relaxation process is shifted to a higher temperature with increasing draw ratio. 

As can be seen, the amorphous phase is not present in all samples and the mass fraction of the interphase decreases as the draw ratio increases. By drawing as many as 150 times, the mass fraction of the interphase becomes as low as 0.06. A sufficient effect of drawing is obtained and the elastic modulus becomes as high as 190 GPa. 

Drawing by hand from a 2-mn spinnerette at about 340°C demonstrated the effectiveness of draw in orienting even a heavily bubbled rod (see Figure 19). From these observations, more controlled drawing experiments were devised, and a weight was attached to the extruding rod as depicted in Figure 18 ... 

FIG. 19.21 Effectiveness of drawing gel-filaments (O) wet filaments (90% residual solvent) ( ) partly dried filaments (6% residual solvent) a = amax (A) dried (extracted) filaments drawing performed single-stage at 120 °C. After Lemstra et al. (1987). 

MECHANICAL PROPERTIES PF PLASTICIZED POLY(VINYL CHLORIDE) EFFECT OF DRAWING AND FILLER ORIENTATION... 

There are some additional applications of the theory which are presently under investigation. These are the effects of drawing on fibers for which the three-dimensional theory with transverse symmetry is applicable and the toughening mechanism in high impact polystyrene for which the flaw spectrum may be viewed as caused by the size, orientation, and spacing distributions of the rubber particles. 

Flgwe 5.9 Effect of drawing or swaging operation on the strength of pearhtic steel wires. Both coarse and fine pearlite show a linear relationship between yield strength and exp (6 4) where e is the strain (after Embury and Fisher, 1966). 

Fig. 12. Effect of draw temperature on the maximum draw ratio attainable (solid line) for high molecular weight (M = 8 X lO ) LPE. Also shown (broken line) the room temperature modulus of samples drawn to the maximum draw ratio at each temperature...

In contrast, much different effects of drawing were observed for the noncrystalline component of PVA fibers, as shown in Fig. 19.11. Here, are the CH resonance lines of the noncrystalline components of PVA fibers spun... 

Draw Oxidation. Hot drawn filaments (X3 at 2500% min-1 at 180°C) were found to photooxidize significantly more rapidly than undrawn fiber, or undrawn fiber exposed to oven heat at 180 °C for the normal draw duration. Solely, thermal oxidation in the oven appeared unimportant. Consequently the effects of draw parameters (temperature and speed) were investigated further. 

Figure 5. Effect of draw atmosphere on PPH photostability. Filaments undrawn (0) or drawn X3 at 1000% min"1 at 25°C in air (+) and vacuum (A).

In the photoageing of polycarbonates, photo-oxidation has been shown to be a more important process than the photo-Fries reaction. The photo-oxidation of epoxy-resins has been found to depend on the type of hardener and its concentration. A correlation has been observed between the changes in chemical structure and thermally stimulated current of poly(vinyl alcohol) during photo-oxidation. Other studies of interest include the weathering of polymers outdoors,effect of ozonation on polymers, effect of drawing, effect of biodegradation, and changes in mechanical properties of thermoplastics. ... 

Addition of hormone to receptors in some instances causes the hormone-receptor complex to dimerize. The tyrosine kinase domains of two such approximated receptor monomers will then become capable of cross-phosphorylation, with a consequent increase in tyrosine kinase activity. The addition of bivalent antibodies would also have the effect of drawing monomeric receptor units together in such a way that they could cross-phosphorylate and thus trigger intracellular effects. 

Effect of Draw Ratio on the Tensile Strength of PVA Fiber... 

The type of enzyme to be used, and quantification of degradation, will depend on the polymer being screened. For example, Mochizukiet studied the effects of draw ratio of polycaprolactone (PCL) fibres on enzymatic hydrolysis by lipase. Degradability of PCL fibres was monitored... 

Mochizuki, M., Hirano, M., Kanmuri, Y., Kudo, K., and Tokiwa, Y., 1995, Hydrolysis of polycaprolactone fibers by lipase - Effects of draw ratio on enzymatic degradation./ Appl. Polym. Sci. 55 289-296. 

Fig. 8. Low density polyethylene. Effect of draw ratio on temperature variation of tan 0 for samples from cold drawn. sheet. (Adapted from Stachurski and Ward. i...

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