Effect of molecular architecture

Since the chemical composition of a polymer defines its flow behavior, we will now explore the effects of molecular architecture, such as chain length, the presence of branching, and polarity on these properties. 

Matsukata, M., Aoki, T., Sanui, K., Ogata, N., Kikuchi, A., Sakurai, Y., and Okano, T. Effect of molecular architecture of poly(Af-isopropylacrylamide)-trypsin conjugates on their solution and enzymatic proporties. Bioconjugate Chem., 1996, 7, 96-101. 

Chung, J. E., M. Yokoyama, T. Aoyagi, Y Sakurai, and T. Okano. 1998. Effect of molecular architecture of hydrophobically modi ed poly(-Jteopropylacrylamide) on the formation of thermo-responsive coreshell micellar drug carriers . Control. Rel.53 119-130. 

Samseth J, Mortensen K, Burns JL, Spontak RJ (1992) Effect of molecular architecture on microstructural characteristics in some polysiloxaneimide multiblock copolymers. J Appl Polym Sci 44 1245... 

JorzikU, Wolf BA (1997) Reduction of the interfacial tension between poly(di-methylsiloxane) and polyethylene oxide) by block copolymers Effects of molecular architecture and chemical composition. Macromolecules 30(16) 4713-4718... 

Given this prescription for parameterization, prototypical lubricants were then explored. One of the first concerns was the investigation of the effects of molecular architecture on viscosity. Such tests were performed by comparing linear alkanes, such as tetracosane (C24) and triacontane ( 30)5 versus a branched alkane squalane (C30, with a 24-carbon-atom backbone).Intuitively, one would expect linear alkanes to have a lower viscosity. Not surprisingly, the simulations showed that the linear alkanes may form layers that... 

A benzyl bromide-type initiator (MI-27) was utilized for the copper-catalyzed synthesis of 3-armed poly(acrylate)s with mesogen units as side-chain groups.324 The effect of molecular architecture on the thermotropic behavior was compared with the corresponding linear polymers in both living and conventional polymerizations. 

Chung JE, Yokoyama M, Aoyagi T, Sakurai Y, Okano T. Effect of molecular architecture of hydrophobically modified poly(iV-isopropylacrylamide) on the formation of thermoresponsive core-shell micellar drug carriers. J Control Release 1998 53 119-130. 

Chiang, Y. C., Jamieson, A. M., Campbell, S., Lin, T., O Sidocky, N. D., Chien, L. C., Kawasumi, M., and Percec, V, The effect of molecular architecture on the electrorheo-logical response of liquid crystal polymers in nematic solvents, Rheol. Acta, 36, 505-512 (1997a). 

LEP Lepilleur, C., Beckman, E.J., Schonemann, H., and Krrrkonis, V.J., Effect of molecular architecture on the phase behavior of fluoroether-functional graft copolymers in supercritical CO2, Fluid Phase Equil, 134, 285, 1997. 

Kuo, C. M. Clarson, S. J. Semiyen, J. A., Studies of Cyclic and Linear Poly(dimethylsiloxanes) 31. Effect of Molecular Architecture/Topology on Blends of Poly(methylphenylsiloxane) and Poly(dimethylsiloxane). Polymer 1994, 35,4623-4626. 

The relaxation exponent Uc may assume values in the range 0 < Wc < 1 (21). Its value cannot be predicted since a systematic study of the effect of molecular architecture on the value of the relaxation exponent is still missing. Typical experimental values are as follows ... 

LiuY, Inoue Y, Sakata S, Kakinoki S, Yamaoka T, Ishihara K. Effects of molecular architecture of phospholipid polymers on surface modification of segmented polyurethanes. J Biomater Sci Polym Ed 2014 25(5) 474-86. 

Samouillan V, Dandurand J, Lacabanne C, Hornebeck W. Molecular mobility of elastin effect of molecular architecture. Biomacromolecules. 2002 3 531-7. 

J. A. Cicero, J. R. Dorgan, J. Garrett, et al. Effects of molecular architecture on two-step melt-spun poly(lactic acid) fibers. J. Appl. Polym. Sci. 2002, 86, 2839-2846. 

Doroszkowski, A., and Lamboume, R. 1978. Effect of molecular architecture of long chain fatty acids on the dispersion properties of titanium dioxide in non-aqueous liquids. Faraday Discuss. Chem. Soc. 65 252. 

In this chapto, we have illustrated the effects of molecular architecture of polysulfobetaines on solution behavior under specilBc environmental conditions of pH, added electrolytes, and polymer concentration. The nature of the comonomer and amount of incorporation of the sulfobetaine within the polymer chain dictate the polymer solubility and solution behavior. Polyampholyte behavior is realized for acrylamide-based systems containing the sulfobetaine moiety. Polyelectrolyte behavior is coupled with polyampholyte behavior for cyclopolymers containing >40mol% sulfobetaine. Incorporation of the sulfobetaine monomer hinders hydrophobic association for the pH responsive copolymers of series TV at low degrees of ionization. 

Kuo, C.M., Clarson, S.J., and Semiyen, J.A. (1994) Studies of cyclic and linear poly(dimethylsiloxane)s 31. Effect of molecular architecture/topology on blends of poly(methylphenylsiloxane) and polyfdimethylsiloxane). Polymer, 35,4623 26. 

Figure 5.15 also compares the effect of molecular architecture as a function of PCL content. All the parameters under consideration (T , T, and X,) are smaller for the PCL phase within the miktoarm stars than within the hnear diblock copolymers at equivalent compositions (same content of PCL), thereby indicating a higher confinement degree for the miktoarm star copolymers. 

Uzum C, Makuska R, von Klitzing R (2012) Effect of molecular architecture on the polyelectrolyte stmctiuing under confinement. Macromolecules 45 3168-3176... 

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