Fillers polymeric

Partially and unreacted also other mineral or polymeric fillers present. 

From the table data one sees that, again, it is carbon or polymeric filler which provides for the maximum degree of crystallinity. 

It should be noted that by immobilizing the metal complex catalysts on carbochain polymers it is possible to prepare polymer-polymer compositions using PVC, PMMA, poly(vinyl acetate), etc., as the polymeric fillers [286-287]. 

It was found that the total fraction of the free-volume in the system increases with increasing concentration of the polymeric filler. The temperature dependence of fg for the epoxy matrix was calculated on the supposition that free-volume is an additive value of the constituent components and using the temperature dependence of the fractional free-volume of polystyrene. It was found that with increasing filler concentration the fractional free-volume becomes greater than for pure epoxy resin. Since the fraction of the free-volume increases with increasing total surface area of the filler, it may be supposed that this effect is associated with the surface layers of polymer. It was found that the rate of free-volume expansion in a filled system is higher than in an unfilled one, which means that the expansivity of the free-volume... 

The effects associated with the influence of the phase border are especially obvious in heterogeneous polymer systems, where both components are of a polymeric nature. Such systems include polymer blends and polymers filled with polymeric filler. These two types of systems differ in that in blends it is difficult to distinguish between the two polymers as a disperse phase and dispersion media due to uniform distribution of both components in the volume. 

From experimental data on viscoelastic properties the fractional free-volume was calculated according to the WLF equation for pure hardened resin, filled with different amounts of polymeric filler obtained from the same hardened resin. By using special methods for preparation of filled specimens, it was possible to obtain... 

Hence, it was of interest to investigate any possible effects of the Ty and modulus of polymeric fillers on the tensile strength of vulcanizates. For this purpose a series of polymeric fillers was prepared by emulsion polymerization, using monomers or mixtures of monomers designed to yield polymers or copolymers of varying Tg and modulus. The experimental details of the polymerization will be described in a forthcoming publication. The characteristics of these polymeric fillers are given in Table I. 

The original objective in preparing emulsion polymers from the 2,6-dichlorostyrene and acenaphthylene was to obtain polymeric fillers of higher Tg than that of polystyrene. It was also presumed that these fillers would not be bonded chemically to the rubber during vulcanization and that the copolymers with butadiene would enable such bonding to be effected. Actually, the polydichlorostyrene and polyacenaphthylene did become bonded to the rubber, as indicated by the inability to extract most of the filler by solvents. The final result was that the copolymers with butadiene served merely as fillers of lower Tg than the above homo-... 

The two systems discussed above demonstrate two mechanisms whereby the tensile strength of elastomers can be reinforced by the presence of rigid fillers. For the polymeric fillers dispersed within a vulcani-zate, the filler operates by raising the viscosity of the matrix, analogous to a decrease in temperature, but without affecting the dynamic, high frequency response (there is ample experimental evidence of the independence of Ty on presence of filler). There is also some indication that the rigidity of the filler affects the extent of reinforcement. 

Figure 40 demonstrates that the 3.5-power law also holds for NR composites with inorganic- and polymeric fillers, respectively. Beside a technical sil-... 

The CCA-model considers the filler network as a result of kinetically cluster-cluster-aggregation, where the size of the fractal network heterogeneity is given by a space-filling condition for the filler clusters [60,63,64,92]. We will summarize the basic assumptions of this approach and extend it by adding additional considerations as well as experimental results. Thereby, we will apply the CCA-model to rubber composites filled with carbon black as well as polymeric filler particles (microgels) of spherical shape and almost mono-disperse size distribution that allow for a better understanding of the mechanisms of rubber reinforcement. 

The metathesis products, the polyalkenamers, exhibit excellent properties as polymeric fillers for elastomers. The interests of the rubber industry stimulate research orientation to this kind of ring-opening polymerization (see, for example, refs. 344-346). 

As with the inorganic fillers, the organic polymers can be successfully used as fillers. The preferred method is the synthesis of polymeric filler in situ, by radical polymerisation, polycondensation or polyaddition processes, developed in liquid polyether media [1-10]. 

These kind of polyether polyols containing polymeric fillers are called polymer polyols and are produced on a large industrial scale, because they are one of the most important group of polyols used for high performance flexible polyurethane (PU) foams and PU elastomers [8-12]. 

Examination of thus prepared heterogeneous membranes showed that they are superior in gas permeabifity to homogeneous ones made of the binder alone. (Permeabifity is a quantity of gas that passed through the unity of area in unity of time at a given difference in gas partial pressure on two sides of the membrane, multiplied by membrane thickness.) As was found, the permeabifity of heterogeneous membranes estimated by H2 depends on the type of polymeric filler and increases in the following order ... 

The disperse crosslinked elastomer phase shows behavior similar to that of a polymeric filler. Viscosity is highly dependent on shear rate [7], but hardly dependent on temperature [7]. The flow exponent is between 3 and 5. 

The properties of filled porous systems must, for a given matrix type, depend on several factors (1) the degree of porosity, (2) the nature of the porosity (size, degree of pore connectivity, shape, and distribution of sizes), (3) the properties of the polymeric filler, including its state, and (4) the nature of the filler-matrix interface. 

These materials have been chosen due to their economic expediency and the valuable combination of physical and chemical, physical and mechanical and other properties of individual polymers - PHB is a brittle thermoplastic PIB - an elastomer. Preparation of composite materials based on combinations of plastics and elastomers is well known plastics are used as polymeric fillers in elastomers, improving their technological and working characteristics elastomers effectively improve strike viscosity and reduce brittleness in compositions based on plastics. 

Vieweg et al. [7] estimated an interface thickness of A 1.5 nm for polymeric fillers (microgels) consisting of cured polybutadiene with a glass transitimi temperature (shear loss factor maximum at frequency 1 Hz) of about 100°C. The filler particles diameters were in between 24 and 75 nm and the sample matrices were commercial statistical styrene-butadiene emulsion copolymers vulcanized with dicumylperoxide. The method they used in [7] was to... 

The 5-ifitrosothiols are generally formed by reaction of nitrous acid with the parent thiol and are reported to require copper-mediated decomposition, reaction with ascorbate, or cleavage by light to release NO. NO donors are incorporated into materials either by blending discrete NO donors within polymeric films or covalently attached to polymer backbones and/or to the inorganic polymeric filler particles that are often employed to enhance the strength of biomedical polymers (e.g., fumed silica or titanium dioxide). ... 

Strategies for Improving Polymeric Filler-Binder Performance for Direct Compression... 

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