Mechanical properties of polymers and composites-Nielsen Episode 9 doc
Mechanical properties of polymers and composites-Nielsen Episode 9 doc
... amorphous polymers is
or. less accurately, using the average value of Au from many polymers, of
4.S x H) ' K \
is the difference between the liquid and glassy volumetric expansion
coefficients and ... ratio of a viscosity to a modulus, as in the spring-dashpot
model of Figure 1, but each sprint! has the same (shear) modulus,
and the steady-flow viscosity T] of equation...
Mechanical properties of polymers and composites-Nielsen Episode 1 doc
... Date
Nielsen. Lawrence E.
Mechanical properties of polymers and composites / Lawrence E.
Nielsen. Robert F. Landel. — 2nd ed., rev. and expanded.
p. cm. — (Mechanical engineering ; 90 )
Includes bibliographical ... theory 297
IK. Theories of Yielding and Cold- Drawing 299
IV. Impact Strength and Tearing 307
A. Nature of impact tesfs 307
B. Effect of notched 308
C. Ef...
Mechanical properties of polymers and composites-Nielsen Episode 2 pot
... bewildering number of mechanical tests and testing instru-
m
ents. Most of these tests are very specialized and have not been officially
recognized as standardized tests. Some of these tests, however, ... variety of
units are used in reporting values of mechanical tests. Stresses, moduli of
elasticity, and other properties are given in such units as MK.S (SI), cgs,...
Mechanical properties of polymers and composites-Nielsen Episode 3 potx
... by the pairs of polymers polypropylene (T g=1 0 C) and
polyisobutylene (Tg = -70 C), and poly(vinyi chloride) (Tg=87 C) and
poly(vinylidene chloride) (Tg =- 19 C). The symmetrical polymers have ... empirical rule and by the pressure dependence of Tg
The empirical rule is (63.64)
where ai and ag arc (he volume coefficients of thermal expansion above
and below Tg, resp...
Mechanical properties of polymers and composites-Nielsen Episode 4 pdf
... York.
194 8.
3. J I), Ferry. Viscoelastic properties of Polymers, 3rd ed., Wiley. New York,
198 0.
4. I , n, Nielsen. Mechanical Properties of Polymers. Van Nostrand Reinhold,
New York. 196 2. ... Polymer Sci., 10, 1351 ( 196 6).
23. ASTM Standards, 31, 1 099 ( 196 9). ASTM STP 463. 2 49 ( 197 0).
24. ASTM Standards D648-56, D/535-65T, and D1637-61, American Society fo...
Mechanical properties of polymers and composites-Nielsen Episode 5 doc
... exactly 90 ° out of phase with the strain. Since
the in-phase component is exactly analogous to thaj of a spring, and the
out -of- phase component to that of a viscous response, the ratio of the
Figure ... all directions. Unoriented amorphous
polymers and annealed glasses are examples of such materials. They have
only one of each of the three kinds of moduli, and sinc...
Mechanical properties of polymers and composites-Nielsen Episode 6 doc
... weight and molecular weight distribution, degree of cross-linking,
and of Plasticization. For two-phase and multiphase systems such as semi-
crystalline polymers and polymer blends, morphology and ... comparisons of the responses of a set of polymers (7,16,54-56).
These frequency/time response curves serve to delineate the effects of
changes in backbone structure (i....
Mechanical properties of polymers and composites-Nielsen Episode 7 pdf
... effect of any change in £
()jr
Copolymers and plasticized materials often show another effect—a
broadening of the transition region with a decrease in the slope of the
modulus curve in the region of ... plateau.
Plasticizers and Copolymerization also shift the glass transition responses
of the amorphous phase of crystalline polymers. In addition, the degree
of Crystallinity...
Mechanical properties of polymers and composites-Nielsen Episode 8 docx
... used.
When the stresses and strains become large and the stress-strain curve
becomes nonlinear, simple descriptions of the response and interconversions
between creep and relaxation become increasingly ... unit, which consists
of a Hookean spring and a Newtonian dashpot in series as shown in the
insert in Figure 1. The modulus or stiffness of the spring is E, and the
viscosi...
Mechanical properties of polymers and composites-Nielsen Episode 10 ppsx
... nitrogen.
Annealing can reduce the creep of crystalline polymers in the same
manner as for glassy polymers ( 89, 94,102). For example, the properties of
a quenched specimen of low-density polyethylene will ... of 0 .98 0. Reid (80,81) has
suggested that for rigid amorphous polymers.
should be proportional
may be related to the
. For brittle polymers, the value of
to
onset...