Solubility of poly

Table 1. Solubility of Poly(Ethylene Oxide) in Several Solvents...

Fig. 4. Water solubility of poly(viayl alcohol) grades, where A represents 78—81 mol % hydrolyzed, DP = 2000-2100 B, 87—89 mol % hydrolyzed,...

The change of solubility of poly(vinyl alcohol) with the degree of acetylation can easily be followed by taking samples at various times and testing their solubility in water, acetone, and methanol. When the degree of acetylation is more than 20 mol% the solubility in water is lost, but the solubility in organic solvents increases. 

A tentative reservation exists about this work. As reported, in a communication, it as yet gives no explanation for the unexpected solubility of poly(r t-butyl isocyanide) in chloroform, nor does it describe a safeguard against the mutual solubility, i.e. plasticization, of polyisocyanides, which is a possibility between the non-crosslinked, otherwise insoluble support medium and the mobile solute. Yet, the rotation data is compelling. 

Materials that typify thermoresponsive behavior are polyethylene- polyethylene glycol) copolymers that are used to fiinchonalize the surfaces of polyethylene films (smart surfaces). When the copolymer is immersed in water, the poly(elhylene glycol) functionalities at the surfaces have solvation behavior similar to poly(ethylene glycol) itself. The ability to design a smart surface in these cases is based on the observed behavior of inverse temperature-dependent solubility of poly(alkene oxidejs in water. 

The theoretical bases for interaction with counterions have been discussed in Sect. 5.1. However, these theories do not take into account the special nature of the ions and only the valency was considered [102-108,114-117]. The solubility caused by the variation in the counterions cannot, for example, be predicted. According to [35] the solubility of poly(diallyldimethylammonium halides) decreases in the order Cl" >Br" >1". The homopolymer precipitates in the iodide form. This is in contrast to ammonium halides where the iodide has the highest solubility [153]. Comparing the effects of Cl", S042", and P043" a very similar in-... 

Low viscosity poly(a-olefins), e.g., 2 and 4 cSt, can be classified as relatively biodegradable in aqueous systems as defined by the CEC L-33-A-93 test however, this does not mean that all poly(a-olefins) are biodegradable. The concept of biodegrability is very difficult to define. The extremely low water solubility of poly(a-olefins) decreases the available surface area for bacterial degradation. If high biodegrabilities are required, linear polyol esters tend to be used. 

Figure 9. Loss of solubility of poly(i-butyl methacrylate) exposed on aluminum foil in single carbon-arc fadeometer, Corex D-filter...

In order to obtain complete solubility of poly(VBPO) and poly(VBPO-co-MMA)s in the HDDA/BA equimolar mixture, UV curing experiments have also been repeated on the same acrylic formulation diluted with chloroform and the results compared with those found for the corresponding low-molecular-weight structural model compound 4-isopropyl-benzoyldiphenylphosphinoxide (IBPO). 

Mertdogan CA, Byun HS, McHugh MA, Tuminello WH. Solubility of poly (tetrafluoroethylen-co-19 mol% hexafluoropropylene) in supercritical CO2 and halogenated supercritical solvents. Macromolecules 1996 29 6548-6555. 

In a suitably chosen mixed solvent system, such as acetic acid and 1-propanol (21), a sharp reversible transition between Form I and Form II can be achieved with a small change in solvent composition. Measurements of optical activity provide a convenient way to follow the transition in dilute solution. There are large changes in optical activity because Forms I and II are helices of opposite handedness. The left panel in Figure 3 depicts the reversible transition that is detected by circular dichroism measurements in mixtures of trifluoroethanol and 1-propanol. Form II is the only conformation present in trifluorethanol. A solution of poly(L-proline) in 35 65 trifluoroethanol 1-propanol exhibits the same circular dichroism pattern as does a solution where the solvent is pure trifluoroethanol. However, further addition of 1-propanol produces a dramatic change in the circular dichroism. At 20 80 trifluoroethanol 1-propanol the circular dichroism pattern is that characteristic of Form I. Data in Figure 3 do not extend beyond 10 90 trifluoroethanol 1-propanol because of the low solubility of poly(L-proline) in 1-propanol. 

Lora, M., Rindfleisch, R, and McHugh, M.A., Influence of the alkyl tail on the solubility of poly(alkyl acrylates) in ethylene and COj at high pressures experiments and modeling, J. Appl. Polym. ScL, 73, 1979-1991, 1999. 

Some solution resins are made via solvent or solution polymerization. This technique of polymerization has been performed in many media that are solvents for monomer but not polymer. Solvents may include methyl alcohol, diethyl ether, dioxane, toluene, benzene, acetone, etc., which may be used singly or as blends. A suitable catalyst for use with methyl alcohol, for example, would be benzoyl peroxide. Hydrogen peroxide may be used with acetone. The resin is separated as a solid by filtering and/or water quenching. This method is usually used for copolymers because of the poor solubility of poly(vinyl chloride). 

MacKey, D. Shiu, W. Y. Aqueous Solubility of Poly-Nuclear Aromatic... 

Due to the low solubility of poly(4-vinyl pyridine) in THF, a block copolymer of 4-vinyl pyridine with styrene has been used (Mn = 13,500). Living polyTHF (Mn = 3,300) has been grafted with efficiencies higher than 95 %. About 20 % of the pyridine units were consumed, yielding a graft copolymer with 80% polyTHF. No further data on this product were reported. 

Figure 9.2 also shows the differing solubility of poly(methyl methacrylate) in the three solvents at a temperature of 303 K. In a good solvent (toluene), the slope or Aj is large, but as the solvent becomes poorer (acetone) Aj decreases, imtil it is zero in the theta-solvent acetonitrile. Thus, Aj provides a useful measure of the thermodynamic quality of the solvent and measures the deviation from ideahty of the polymer solution. 

SAN Sander, U. and Wolf, B.A, Solubility of poly(n-afkylmethacrylate)s in hydrocarbons and in alcohols,Makromol. Chem., 139,149,1986. 

MIS Mishima, K., Matsuyama, K., and Nagatani, M., Solubilities of poly(ethylene glycol)s in the mixtures of supercritical carbon dioxide and cosolvent, Fluid Phase Equii, 161, 315, 1999. 

KHO Khosravi-Darani, K., Vasheghani-Farahani, E., Yamini, Y., and Bahramifar, N., Solubility of poly(beta-hydroxybulyrate) in supercritical carbon dioxide, J. Chem. Eng. Data, 48, 860, 2003. 

Table II. Optical properties and solubilities of poly(aromatic oxadiazoles) 18-20...

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