Another consideration is the difference in thermal expansion between the matrix and the reinforcement. Composites are usually manufactured at high temperatures. On cooling any mismatch in the thermal expansion between the reinforcement and the matrix results in residual mismatch stresses in the composite. These stresses can be either beneficial or detrimental if they are tensile, they can aid debonding of the interface if they are compressive, they can retard debonding, which can then lead to bridge failure (25). [Pg.48]

The results of Jamieson and McNeill cannot be accounted for by the intramolecular mechanism proposed by Grassie and coworkers [136,137] for the thermal degradation behavior of VC/VAc copolymers (Eqs, [28] and [29]). They can be accounted for much more convincingly by the alternative approach proposed by Naqvi based on polar interactions within the PVC matrix. Just like in copolymers even in blends, the polar carbonyl group of PVAc intensifies the concentration of like-poles in the PVC matrix resulting in destabilization. [Pg.332]

The study of the mechanical properties of filled elastomer systems is a chaUenging and exciting topic for both fundamental science and industrial application. It is known that the addition of hard particulates to a soft elastomer matrix results in properties that do not follow a straightforward mle of mixtures. Research efforts in this area have shown that the properties of filled elastomers are influenced by the nature of both the filler and the matrix, as well as the interactions between them. Several articles have reviewed the influence of fiUers hke sihca and carbon black on the reinforcement of elastomers.In general, the strucmre-property relationships developed for filled elastomers have evolved into the foUowing major areas FiUer structure, hydrodynamic reinforcement, and interactions between fiUers and elastomers. [Pg.503]

Metal derivatives (Ti, Zn, Cd, Sn, Sb, Pb) and bromine from additives in recycled thermoplasts from consumer electronic waste were determined by dissolving the samples in an organic solvent, followed by TXRF analysis [56], The procedure proved considerably less time-consuming than conventional digestion of the polymer matrix. Results were validated independently by INAA. [Pg.639]

The appearance and persistence of core-shell structures as well as the occurrence of phase separation are attributed to a small asymmetry in the X -parameters (xPS-pi = 0.06, xpi-pdms = 0.09 and xps-pdms = 0.20). Hence, a PDMS core surrounded by a PI shell embedded in a PS matrix results in a smaller inner diameter interfacial area, relative to that for the PS-PI case. In a blend of a PS-fo-PI-fc-PDMS triblock with PS and PDMS homopolymers, more PS homopolymer is expected to be found in the corona of the PS block than PDMS homopolymer in the corona of the PDMS block because the penalty for contact between the PI block and PDMS homopolymer is larger. In consequence, the distribution of homopolymers favours an expanded PS-PI interface, making the core-shell morphologies, gyroid and cylinder, more prevalent. [Pg.206]

A significant suppression of the yellow emission band of LPPP was also achieved by dilution in PVK matrix, resulting in 2-3 times increase in EL efficiency, compared to the device prepared with neat LPPP (ITO/polymer/Al) [622]. [Pg.223]

Note that because the columns of T happen to be orthogonal, the linear transformation matrix results in a diagonal form for MT. The reaction rate functions in the transformed chemical source term then act on each of the transformed scalars individually.21... [Pg.167]

Then, the first order relaxation matrix results in an uncoupled system of differential equations with the diagonal form ... [Pg.238]

The second phase of Ledet s algorithm is carried out on the reordered occurrence matrix resulting from the first phase of the algorithm described immediately above. Because the second phase is quite complex, it will not be discussed here, but the details can be found in the original reference. Ledet shows that in most cases the first phase of the algorithm will obtain the minimum number of tears, or very nearly the minimum number of tears, and that the extra effort of executing the second phase is seldom justified. [Pg.218]

Within a composite material, much of the ultimate strength comes from the intimate contact the fiber has with the matrix material. Nanofibers allow more contact between the fiber (on a weight basis) and the matrix resulting is a stronger composite because of an increased fiber surface matrix interface. [Pg.249]

The low H/C-ratio of FCC feed derived from liquefied biomass led to low conversion and poor gasoline selectivity. Addition of alumina to the matrix resulted in a catalyst more active for heavy oil cracking but with a poor selectivity. Alumina-montmorillonite catalysts showed activities for heavy oil cracking comparable to that of a conventional, zeolite based, cracking catalyst. Effects of matrix composition and zeolite type on the heavy oil cracking performance are discussed. [Pg.266]

In isosmotlc solutions, movement of neutral amino acids such as prollne across the inner membrane into the matrix results in swelling of mitochondria (20). As shown in Figure 3C, the movement of proline is thought to occur via a uniport. The increased concentration of proline in the matrix produces an osmotic-induced swelling. Kinetics of the swelling response is shown in the 0 (control) trace. Again, quercetin inhibited this response in a concentration-dependent manner. [Pg.258]

The nature of soil-phenolic acid interaction adsorption-desorption. Adsorption of a solute from solution onto a solid matrix results in a higher solute concentration at the fluid-solid interface than in the solution. Huang and coworkers (27) observed a high sorption capacity of the mineral fraction of four latosols for phenolic acids. On the basis of their results, distribution coefficients,... [Pg.361]

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