Influence of plasticizers

Despite the fact that a great lot of ion-selective electrodes (ISEs) with liquid and film polymeric membranes for the determination of physiologically active amines (PhAA) has been described, the factors responsible for their selectivity have not yet been studied sufficiently. In this work, the influence of plasticizer and ion-exchanger nature on the selectivity of ISEs reversible to PhAA cations of various stmctures has been discussed. 

In the preparation and processing of ionomers, plasticizers may be added to reduce viscosity at elevated temperatures and to permit easier processing. These plasticizers have an effect, as well, on the mechanical properties, both in the rubbery state and in the glassy state these effects depend on the composition of the ionomer, the polar or nonpolar nature of the plasticizer and on the concentration. Many studies have been carried out on plasticized ionomers and on the influence of plasticizer on viscoelastic and relaxation behavior and a review of this subject has been given 119]. However, there is still relatively little information on effects of plasticizer type and concentration on specific mechanical properties of ionomers in the glassy state or solid state. 

In the early literature it is suggested that polycarbonates can be easily plasticized with common plasticizers. Plasticization of polycarbonate has been investigated by Kozlov et al. (12). These authors described the influence of plasticization on softening points and mechanical properties of bisphenol A polycarbonates. They conclude that the behavior of plasticized polycarbonate is similar to that encountered for most amorphous polymers. The influence of crystallization effects promoted by the plasticizer was not taken into account. 

In this study the influence of plasticizer content on the rate of crystallization was briefly investigated. The time needed for the first spherulites to appear on heating the plasticized polymer at 190°C. was used as a rough indication of the crystallization tendency. 

The influence of plastic deformation on the reaction kinetics is twofold. 1) Plastic deformation occurs mainly through the formation and motion of dislocations. Since dislocations provide one dimensional paths (pipes) of enhanced mobility, they may alter the transport coefficients of the structure elements, with respect to both magnitude and direction. 2) They may thereby decisively affect the nucleation rate of supersaturated components and thus determine the sites of precipitation. However, there is a further influence which plastic deformations have on the kinetics of reactions. If moving dislocations intersect each other, they release point defects into the bulk crystal. The resulting increase in point defect concentration changes the atomic mobility of the components. Let us remember that supersaturated point defects may be annihilated by the climb of edge dislocations (see Section 3.4). By and large, one expects that plasticity will noticeably affect the reactivity of solids. 

Meier, M. M., Kanis, L. A., and Soldi, V. (2004), Characterization and drug-permeation profiles of microporous and dense cellulose acetate membranes Influence of plasticizer and pore forming agent, Int. J. Pharm., 278, 99-110. 

No.26, 1998, p.6755-65 INFLUENCE OF PLASTICIZER CONFIGURATIONAL CHANGES ON THE MECHANICAL PROPERTIES OF HIGHLY PLASTICIZED POLY(VINYL CHLORIDE)... 

Yet, for systems A and C, the measured fracture energies remain low compared with the critical fracture energy of the bulk aluminum 10 J Moreover, we do not observe islands of passivation material on the A1 fracture surface and, inversely, we do not observe A1 on debonded surfaces of the passivation films. This suggests that the loss of interfacial adhesion is close to a brittle fracture process despite the influence of plasticity of the A1 substrate and crack blunting at the interface. This sort of brittle mode of interfacial failure, including plastic flow in a ductile material (the substrate), has been observed or discussed for a sapphire/Au interface. ... 

Amighi, K. Moes, A. Influence of plasticizer concentration and storage conditions on the drug release rate from Eudragit RD30D fihn-coated sustained-release theophylline pellets. Fur. J. Pharm. Biopharm. 1996, 42 (1), 29-35. 

Wesshng, M. Bodmeier, R. Influence of plasticization time, curing conditions, storage time, and core properties on the drug release from aquacoat-coated pellets. Pharm. Dev. Technol. 2001, 6 (3), 325-331. 

Felton, L.A. McGinity, J.W. Influence of plasticizers on the adhesive properties of an acryhc resin copolymer to hydrophilic and hydrophobic tablet compacts. Int. J. 

Table 5 Influence of plasticizers and drugs on tensile strength (TS), percent elongation (%E), and Young s modulus (YM) of HPC extruded films stored at 25° C...

Repka, M.A. Gerding, T.G. Repka, S.L. McGinity, J.W. Influence of plasticizers and drugs on the physical-mechanical properties of hydroxypropylcellulose films prepared by hot-melt extmsion. Drug Dev. Ind Pharm. 1999,25 (5), 627-635. 

The study of the influence of plasticizer on physical-mechanical properties of ME is presented in Table 3. Introduction of plasticizer causes elongation increase (up to 1100 %) and reduction of elasticity (up to 1.7 kPa) at the same time. 

Rao PR, Diwan PV. Permeability studies of cellulose acetate free films for transdermal use influences of plasticizers. Pharm Acta Helv 1997 72 47-51. 

Williams RO, Wheatley TA, Liu J. Influence of plasticization and curing conditions on the mechanical properties of aqueous based cellulose acetate films. STP Pharma Set 1999 9(6) 545—553. 

This test method was proposed by Senbetta16. Its original purpose was to evaluate the impact resistance of floor materials in terms of the capacity to resist surface disintegration due to repetitive low level impact. Instead of floor materials, this test was employed to measure the influence of plastic fillers on the concrete resistance to repetitive low impact. The specimens which were used in the test were nine 2-in. (50-mm) concrete cubes made with mix No. 2. The test uses the Los Angeles (LA) abrasion machine, which is traditionally utihzed to test aggregates according to ASTM C 131 and C 535 specifications. 

A large amount of phenols is released in wastewater and can be lost to waste streams. A rapid increase in the distribution and abundance of plastic debris in the ocean around the world was reported, and the adverse influence of plastic s phenol residues has been of great interest Polluted water disinfection, enzymatic oxidation of chlorinated phenols, decomposition of alkylphenol polyethoxylates and combustion of phenols can lead to the formation of highly toxic compounds. High adsorption of phenols on sludge and sediments requires that their distribution in these systems also be followed. All of these facts have promoted extensive research on phenolic compounds and their fate in the environment. 

Abstract The work is devoted to the study of influence of plastic deformation on... 

For a very thin specimen i.e., with B (Kjc/ays) ), the influence of plastic deformation at the surfaces will relieve crack-tip constraint through the entire thickness of the specimen before Kj reaches Kjc. As such, the opening mode of fracture is suppressed in favor of local deformation and a tearing mode of fracture. The behavior is reflected in the load-displacement record by a gradual change in slope and final fracture, which could still be abrupt (see Fig. 4.7b), but the conditions of plane strain would not be achieved. 

Figure 3. Influence of plasticizer molecular weight on PVC compatibility related to dielectric constant (17).

The influence of plasticizers on the mechanical properties of PLA has been extensively studied. Various plasticizers have been tested with PLA such as, glycerol, PLA oligomers, poly(ethylene glycol) monolaurate [98],... 

Zhu, Y. Mehta, K.A. McGinity, J.W. Influence of plasticizer level on the drug release from sustained release film coated and hot-melt extruded dosage forms. Pharm. Dev. Technol. 2006, 77(3), 285-294. 

Schilling, S.U. Lirola, H.L. Shah, N.H. Waseem Malick, A. McGinity, J.W. Influence of plasticizer type and level on the properties of Eudragit SlOO matrix pellets prepared by hot-melt extrusion. J. Microencap. 2010, 27(6), 521-532. 

Audic, J.L., Chaufer, B. Influence of plasticizers and cross linking on the properties of biodegradable films made from sodium caseinate. Etir. Polymer J. 41, 1934-1942 (2005)... 

M. M. Reddy, M. Misra, A. K. Mohanty. Biodegradable Blends from Com Gluten Meal and Poly (butylene adipate-co-terephthalate)(PBAT) Studies on the Influence of Plasticization and Destmcturization on Rheology, Tensile Properties and Interfacial Interactions , J. Polym. Environ., 22, 167-175 (2014) ... 

Gelation and fusion of PVC plastisols can be studied by different techniques classified as statical and dynamic methods. Among the dynamic methods, rheological characterization has shown to be a reliable technique of study. Using dynamic methods the influence of plasticizer concentration and type and the influence of the resin type (characteristic molecular weight and particle size distribution) were analyzed. The most relevant findings are discussed below. 

INFLUENCE OF PLASTICIZERS ON THE GLASS TRANSITION TEMPERATURE OF POLYMERS... 

Influence of plasticizers on the glass transition temperature of polymers... 

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