Effect of Reinforcements

Very recently, Williams, Billington Pearson (1992) have examined the effect of reinforcement by silver or silver-tin alloy on the mechanical properties of three glass-ionomer cements. Measurements of compressive, flexural, tensile (measured by the diametral compressive procedure) and shell strength are given in Table 5.17. These results show that the effect of reinforcement varies from cement to cement but, in general, increases it. 

Table 5.17. Effect of reinforcement on various strength properties of three glass polyalkenoate cements Williams, Billington Pearson, 1992)...

The value of TMWV is dependent on the cohesive energy density (CED) of amorphous polymers, the extent of crystallinity in crystalline polymers, and the effect of reinforcements in polymeric composites. Thus, while a low molecular weight amorphous polymer may be satisfactory for use as a coating or adhesive, a chain length generally above 100 is often required if the polymer is to be used as an elastomer or plastic. 

Curran C, Byrappa N McBride A (2004). Stimulant psychosis systematic review. British Journal of Psychiatry, 185, 196-204 Dallery J, Silverman K, Chutuape MA, Bigelow GE Stitzer ML (2001). Voucher-based reinforcement of opiate plus cocaine abstinence in treatment-resistant methadone patients effects of reinforcer magnitude. Experimental and Clinical Psychopharmacology, 9, 317-25... 

From the technological standpoint, numerous empirical parameters have been used to characterize the effect of reinforcement. Two of them based on rheometry and filler-elastomer interactions will be discussed the aF parameter17) and the reinforcement factor RF ]8 20). 

Kandola, B. K., Horrocks, A. R., and Rashid, M. R. Effect of reinforcing element on burning behaviour of fibre—Reinforced epoxy composites, Proceedings of 17th Annual BCC Conference on Flame Retardancy, Stamford, CT, May 22-24, 2006. 

The notion of incentive arousal described here is similar to that of the incentive state of some early incentive theorists, particularly Cofer (1972) and Killeen (1975) and corresponds to the classic notion of behavioral arousing as distinct from directional effects of reinforcers. An incentive role of reinforcers related to their behavioral arousing influences was assumed to be the mechanism by which stimuli exert Pavlovian... 

Rescorla RA, Wagner AR (1972) A Theory of Pavlovian conditioning Variations in the effectiveness of reinforcement and non-reinforcement. In Black AH, Prokasy WF (Eds), Classical Conditioning 77 Current research and theory, pp. 64-99. Appleton-Century-Crofts, New York. 

Considerable effort has been spent to explain the effect of reinforcement of elastomers by active fillers. Apparently, several factors contribute to the property improvements for filled elastomers such as, e.g., elastomer-filler and filler-filler interactions, aggregation of filler particles, network structure composed of different types of junctions, an increase of the intrinsic chain deformation in the elastomer matrix compared with that of macroscopic strain and some others factors [39-44]. The author does not pretend to provide a comprehensive explanation of the effect of reinforcement. One way of looking at the reinforcement phenomenon is given below. An attempt is made to find qualitative relations between some mechanical properties of filled PDMS on the one hand and properties of the host matrix, i.e., chain dynamics in the adsorption layer and network structure in the elastomer phase outside the adsorption layer, on the other hand. The influence of filler-filler interactions is also of importance for the improvement of mechanical properties of silicon rubbers (especially at low deformation), but is not included in the present paper. 

Table 51 Effect of Reinforcements on Mechanical Properties of Foamed Composite, Airlite FRU Classified by Fiber Efficiency Factor (2)... 

Greenberg, M. E, and Weiner, B. B. (1966), "Effects of reinforcement history upon risk-taking behavior," Journal of Experimental Psychology 71,587-92. 

Gating and venting must be done with an eye to the effects of reinforcement orientation and bubble track formation downstream of flow obstructions. The size and number of vents required depends upon the volume of the part and the rate of fill used in addition to the shape of the part itself. Preferred vent geometry is a groove. 003-.005 inches deep and 3/8 inches wide. This does not permit excessive flash and polymerizes closed rather quickly. 

Delmas PD, Vrijens B, van de Langerijt L, Roux C, Eastell R, Ringe JD, et al. 2003. Effect of reinforcement with bone turnover marker results on persistence with risedronate treatment in postmenopausal... 

Equation 7.20 shows that the changes in mechanical properties are first affected by temperature and then by the network of unstable links. Only after the unstable links are consumed stable links take the impact of changes occurring in the material. A similar logic can be applied to show that filler concentration also plays an essential role, considering that with small addition of filler most chains will form weak bonds because of very high competition for free surfaces on filler particles and the effect of reinforcement will be diminished. This is expressed by a simple equation ... 

Gaian D and Lynch E (1989) The effect of reinforcing fibres in denture acrylics. J Irish Dent Assoc 35 109-113... 

Figure 4.14 Minimizing the effect of reinforcing steel on four probe resistivity measurements when the probe array is bigger than the reinforcement spacing.

Effect of reinforcement of polypropylene with lignocellulosic materials on the acoustic properties... 

Sin Singh, R. P., Zhang, M., Chan, D. Toughening of a brittle thermosetting polymer Effects of reinforcement particle size and volume fraction. J. Mater. Sci. 37 (2002) 781-788. 

Almost as critical in commercial practice as the effects of reinforcement on proi>erties are the effects of reinforcement on the cost of the material and on its processing. The perceived effect of material cost depends on whether the decisive factor is cost per unit mass or cost per unit volume. Since the additive normally has a density considerably different from that of the po er matrix, the density of the composite differs from that of the polymer. Consider the fibre-reinforced polymer shown schematically in Figure 6.4. A mass m of composite occupies a volume u. It contains a mass of fibres occupying a volume and a mass of matrix occupying a... 

Effect of Reinforcing Agents, Fillers and Flame Retardants on Polymer Properties... 

Val V. D. et al. 1998. Effects of reinforcement corrosion on reliability of highway bridges. Engineering Structures. 1998. 

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