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Relaxation maxima

Figure 4.2 shows the DMA results of a PP/talc (85/15) system represented in the standard way i.e. the log G and log G plotted as a function of the temperature. The loss shear modulus curve shows relaxation maxima at about 60°C (the crystalline phase [a] relaxation) and at about 0°C the amorphous phase glass-rubber [S] relaxation). Blending such a PP sample with a C2C3 rubber results in an extra (rubber) relaxation maximum at about -50°C. [Pg.97]

A reproducible base-line drawing procedure and a kind of peak deconvolution procedure is necessary to determine the area of this rubber loss maximum and that of the original PP relaxation maxima. A computerised deconvolution program for the separation of overlapping DMA loss maxima was described by... [Pg.97]

The dielectrically measured relaxation maxima are plotted in an Arrhenius plot together with the DMA data (9.3.2) and the result of the Tg(midpoint) determination by DSC (9.3.3),... [Pg.331]

Mechanical Damping. The elastic energy behavior of resins at low temperatures was determined from the stress-strain relation. Small inelastic contributions, not detectable with that method can be determined by damping measurements using a free torsion pendulum. The mechanical loss, tan 8m, is plotted vs. temperature in Fig. 10. Low-temperature values were similar for the resins considered. No major structural dependence is indicated. (It is not within the scope of this paper to consider the relaxation maxima of resins.)... [Pg.25]

Fig. 54. Variations in P-relaxation maxima for PCL ( ) and phenoxy (A) in PCL/phenoxy blends adapted from [138]... Fig. 54. Variations in P-relaxation maxima for PCL ( ) and phenoxy (A) in PCL/phenoxy blends adapted from [138]...
RESOLUTION OF RELAXATION MAXIMA IN TWO-PHASE POLYMERIC SYSTEM... [Pg.219]

Similar results were obtained for mixtures of polyurethane and PVC and poly(e-caprolactone) with styrene-acrylonitrile copolymer. It was found that fillers (silica, carbon black, and talc) broaden the rubbery PU transition, shifting it to higher temperatures. This effect was found to be less pronounced for the high temperature PVC relaxation. The positions of the relaxation maxima are shifted... [Pg.341]

However, in order to postulate a compatibilizing action, one must observe a remarkable broadening of the maxima of relaxation or two relaxation maxima eroding into one maximum. Such effects are much more pronounced for filled interpenetrating polymer networks (see 7.5 ). [Pg.343]

Resolution of relaxation maxima in two-phase polymeric system 219... [Pg.412]

Rosovitsky V F and Lipatov Y S (1985) To determination of segregation degree in two phase polymer systems on parameters of relaxation maxima. Reports Acad Sci USSR 283 910-913 (in Russian). [Pg.354]

Determining the Segregation Degree from Parameters of Relaxation Maxima... [Pg.139]

The IPNs, as a rule, undergo in the course of curing nonequilibrium microphase separation due to thermodynamic incompatibility of the constituent networks. IPNs present two-phase systems with phases of varying composition. All such systems are characterized by the existence of two relaxation maxima corresponding to the constituent phases. Up to now there are only scattered works where the compatibilization of IPNs is considered. The improvement of compatibility of two networks comprising IPNs may be reached either by grafting one network to the other [148,336-339] or by introducing compatibilizers of the same type, as were used for blends of linear polymers [339,340]. [Pg.201]

Diminishing of the heights of the relaxation maxima of PU and PS constituents, their approaching and broadening, as well the increasing level of losses between maxima may testify to diminishing amounts of the two phases due to transition of some part of PU and PS into the interfacial region as a result of interaction with OUDM. [Pg.211]


See other pages where Relaxation maxima is mentioned: [Pg.119]    [Pg.370]    [Pg.99]    [Pg.84]    [Pg.590]    [Pg.340]    [Pg.353]    [Pg.353]    [Pg.355]    [Pg.70]    [Pg.189]    [Pg.189]    [Pg.231]    [Pg.260]    [Pg.269]    [Pg.2]    [Pg.111]    [Pg.130]    [Pg.132]    [Pg.140]    [Pg.200]    [Pg.210]    [Pg.211]    [Pg.216]    [Pg.217]   
See also in sourсe #XX -- [ Pg.269 ]




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