Poly ethylene oxide macromonomers

Ito K (1994) In Macromolecular design concept and practice, macromonomers, chap 4 Poly(ethylene oxide) macromonomers. Polymers Frontiers International... 

So far, there have been only few reports about the synthesis of amphipolar polymer brushes, i.e. with amphiphilic block copolymer side chains. Gna-nou et al. [115] first reported the ROMP of norbornenoyl-endfunctionalized polystyrene-f -poly(ethylene oxide) macromonomers. Due to the low degree of polymerization, the polymacromonomer adopted a star-like rather than a cylindrical shape. Schmidt et al. [123] synthesized amphipolar cylindrical brushes with poly(2-vinylpyridine)-block-polystyrene side chains via radical polymerization of the corresponding block macromonomer. A similar polymer brush with poly(a-methylstyrene)-Wocfc-poly(2-vinylpyridine) side chains was also synthesized by Ishizu et al. via radical polymerization [124]. Using the grafting from approach, Muller et al. [121, 125] synthesized... 

Fig. 6 Left Elaboration of silica/polystyrene raspberry-like colloids through emulsion polymerization using a MMA-terminated poly(ethylene oxide) macromonomer (PEGMA) as coupling agent. Right SEM and TEM pictures of the raspberry-like particles. Adapted from [40] with permission of American Chemical Society...

Figure 1. Preparation of norbornene functionalised poly (ethylene oxide) macromonomer.

DISPERSION POLYMERIZATION OF STYRENE IN AQUEOUS ETHANOL MEDIA USING POLY(ETHYLENE OXIDE) MACROMONOMER AS A POLYMERIZABLE STABILIZER... 

The dispersion polymerisation of styrene was studied in a mixed ethanol-water medium using 0.1-2 wt% of omega-methoxy poly(ethylene oxide)40 undecyl-alpha-methacrylate macromonomer as a steric stabiliser. The polymerisation rate reached a maximum at a styrene conversion of around 18% and remained almost constant up to about 55% conversion. The molecular weight of the polymer increased with increasing conversion of styrene up to about 55%. The polymerisation rate and activation energies were studied and discussed. Spherical monodisperse particles of around 250 nm diameter were obtained for the final stable latices.The grafted poly(ethylene oxide) macromonomers were enriched and anchored on the surface of PS latex particles with a top surface composition of 28% macromonomer. 33 refs. SINGAPORE Accession no.665916... 

A poly(ethylene oxide) macromonomer containing a 2-oxazoline group at... 

Of relevance to this section, Reculusa et al. also recently demonstrated that the addition of a small amount (only 1.5 pmole/m ) of a monomethylether mono methylmethacrylate poly(ethylene oxide) macromonomer (structure 9, Table 4.5) allowed the direct self-assembly of nanometric polystyrene latex particles on the surface of submicronic sihca particles through an in-situ nucleation and growth process (Fig. 4.12) [102]. The two sets of particles were assembled in a raspberry-like morphology via the formation of hydrogen bonds at the interface of the inorganic and organic coUoids. The size and shape of the assembly can be easily controlled by varying the sizes and stoichiometries of the colloidal components (Fig. 4.13). 

Gong, L.H. Gan, The partide size of latexes from dispersion polymerization of styrene using poly(ethylene oxide) macromonomers as a polymerizable stabi-... 

Rhousakoun, E., Cohy, J.F. and Jerome, R. (2004) Self-association of double-hydrophUic copolymers of acryhc acid and poly(ethylene oxide) macromonomers. Polymer, 45,8303-8310. 

Liu J, Teo WK, Chew CH, Gan LM. Nanofiltration membranes prepared by direct microemulsion copolymerization using poly(ethylene oxide) macromonomer as a polymerizable surfactant. J Appl Polym Sci 2000 77 2785-2794. 

Kawaguchi S, Winnik MA, Ito K. Dispersion copolymerization of n-butyl methacrylate with poly(ethylene oxide) macromonomers in methanol-water, comparison of experiment with theory. Macromolecules 1995 28 1159-1166. 

An alternative procedure has been utilized to prepare 1,1-diphenylethy-lene-functionalized poly(ethylene oxide) macromonomers as shown in Scheme27 [210, 211]. This macromonomer (81) reacted quantitatively with poly(styryl)lithium to form the corresponding living diblock copolymer adduct. After cooling to 5 °C, ferf-butyl methacrylate was added and polymerized for ca. 2h. After quenching with acidic methanol, the hetero, threearmed, star-branched, ABC-type block copolymer was isolated. The molecular weight determined by SEC (universal calibration M = 19,500 M /M =1.14) and by H NMR (M =17,300) were somewhat higher than the calculated value (M = 15,500) [211]. 

As polymers that contain both hydrophilic and hydrophobic components aroused keen interest from theoretical and practical points of view over the past years, synthesis of amphiphilic branched copolymers by ring-opening metathesis polymerization of miscellaneous macromonomers is an important goal of the actual research. Thus, in order to obtain globular shape macromolecules that would present the same features as those exhibited by certain assemblies of molecules such as the micelles or the latices, with a bulk part different from the external surface, polymerization of norbornyl polystyrene-poly(ethylene oxide) macromonomer has been conducted in the presence of Schrock-type catalyst Mo(NAr)(CH/Bu)(OC(CH3)(CF3)2)2 in toluene at room temperature to produce poly-norbornene-polystyrene-poly(ethylene oxide) block copolymers (120) [88] [Eq. (52)]. 

It is noteworthy that polymers of practical interest that exhibit a globular shape and unsymmetrical faces of the Janus-type architecture, not easy to make by conventional methods [89, 90], can be prepared by sequential ring-opening metathesis copolymerization of two different norbomenyl macromonomers. To this end, sequential polymerization of co-norbomyl polystyrene and a-norbornyl-poly(ethylene oxide) macromonomers in the presence of the Schrock initiator Mo(NAr)(ChrBu)(OC(CH3)(CF3)2)2 produced poly[polystyrene xycarbonyl-norbornene)-b-poly(ethylene oxide) xymethylene-norbomene)] block copolymer (122) in high yield [88] [Eq. (54)]. 

The products obtained under these conditions displayed high molecular weights and polydispersities indexes lower than 1.3. In addition, statistical poly[polystyrene-oxycarbonyl-norbornene)-b-poly(-ethylene oxide)-oxymethylene-polynorbornene)] copolymers were obtained from co-norbomyl-poly-styrene and ot-norbornyl-poly(ethylene oxide) macromonomers by copolymerization under similar conditions. The distribution of PS and PEO grafts along the polymer backbone and the tendency of the copolymerization to blockiness in this case were determined by the reactivity ratios of the two macromonomers. 

Poly(dimethylsiloxane) and poly(ethylene oxide) macromonomers were commercial products.PCL macromonomer was obtained in reaction of the terminal hydroxyl end-groups of PCL with methacryloyl chloride. Poly(D,L-lactide) methacrylate was obtained by using 2-hydroxyethyl methacrylate as an initiator of the D,L-lactide polymerization and stannous acrylate as a catalyst. 

Macromonomers can be obtained by similar means, as illustrated below with the example of co-methacryloyl poly(ethylene oxide) macromonomer ... 

Cell-polymer interactions of fluorescent polystyrene (FPS) latex particles coated with thermosensitive PNIPAM and poly(N-vinylcaprolactam) or grafted with poly(ethylene oxide)-macromonomer were analyzed by Vihola et al. [131] by modifying the surface of the FPS particles with the thermosensitive polymer gels or with poly(ethylene oxide)-macromonomer grafts. In all the cases, the FPS were surface-modified by polymerization of both thermosensitive monomers and macromonomer onto the surface of the fluorescent particles. The final surface-coated particles have potential biotechnological applications in the form of either stealth-carrier behavior or enhanced cellular contact. 

Gibanel, S., Heroguez, V., Forcada, J., and Gnanou, Y. 2002. Dispersion polymerization of styrene in ethanol-water mixture using polystyrene-b-poly(ethylene oxide) macromonomers as stabilizers. 

Vihola, H., Martila, A.K., Pakkanen, J.S., Andersson, M., Laukkanen, A., Kaukonen, A.M., Tenhu, H., and Hirvonen, J. 2007. Cell-polymer interactions of fluorescent polystyrene latex particles coated with thermosensitive poly(Ar-isopropylacrylamide) and poly(A-vinylcaprolactam) or grafted with poly(ethylene oxide)-macromonomer. Int. J. Pharm. 343 238-46. 

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