Methacryloyl group

Terminal-functionalized polymers such as macromonomers and telechelics are very important as prepolymer for construction of functional materials. Single-step functionalization of polymer terminal was achieved via lipase catalysis. Alcohols could initiate the ring-opening polymerizahon of lactones by lipase catalyst. The lipase CA-catalyzed polymerizahon of DDL in the presence of 2-hydroxyethyl methacrylate gave the methacryl-type polyester macromonomer, in which 2-hydroxyethyl methacrylate acted as initiator to introduce the methacryloyl group quanhtatively at the polymer terminal ( inihator method ).This methodology was expanded to the synthesis of oo-alkenyl- and alkynyl-type macromonomers by using 5-hexen-l-ol and 5-hexyn-l-ol as initiator, respechvely. 

End-functional polymers were also synthesized by lipase-catalyzed polymerization of DDL in the presence of vinyl esters [103,104]. The vinyl ester acted as terminator ( terminator method ). In using vinyl methacrylate (12.5 mol % or 15 mol % based on DDL) and lipase PF as terminator and catalyst, respectively, the quantitative introduction of methacryloyl group at the polymer terminal was achieved to give the methacryl-type macromonomer (Fig. 12). By the addition of divinyl sebacate, the telechelic polyester having a carboxylic acid group at both ends was obtained. 

All four types of polymerizable lipids shown in Fig. 4 have been realized synthetically. In this context, one need not attempt to reproduce mother nature slavishly (Fendler 8)). Kunitake 9) was able to show that simple molecules like dialkyldimethyl-ammonium salts also form bilayer assemblies. Fuhrhop 10) and Kunitake U) could accomplish the formation of monolayer liposomes with molecules containing only one alkyl chain and two hydrophilic head groups. Acryloylic and methacryloylic groups (type a and d, Table 1), as well as diacetylenic, butadienic, vinylic and maleic acid groups (type b and c), have been used as polymerizable moieties. A compilation of amphiphilic, photopolymerizable molecules is given in Table 1. 

The subsequent step generally involves reaction with glycidyl methacrylate. The resulting macromolecule bears a methacryloyl group at the chain end the olefine double bond of which may be polymerized ... 

Anionic homopolymerization of poly-THF macromonomers bearing terminal styryl, a-methylstyryl or methacryloyl groups has not been reported so far. 

The polyisobutene macromonomers bearing a methacryloyl group at both chain ends have not been copolymerized so far. Yet this would provide a route to a new kind of tailor-made networks. 

The polymerizable groups include methacryloyl, styrenic, epoxide, vinyl ether, and others, among which the methacryloyl-capped macromonomers are most widely available from vinyl ethers, styrene, and its derivatives. For example, the a-end methacryloyl group can be introduced by the functional initiator method, with the hydrogen halide-adduct of 2-... 

A number of hyperbranched systems have been prepared. These include polyimides with methacryloyl groups at the chain ends, methacrylated polyamine esters, " polyurethane acrylates, polyester acrylates and polyisoph-thalate esters. All materials exhibit 3D sphere like structures with excellent properties. 

A number of hyperbranched systems have been prepared. These include polyimides with methacryloyl groups at the chain ends, methacrylated... 

Nagasaki, Y., Ogawa, R., Yamamoto, Kato, M., and Kataoka, K., Synthesis of Heterotelechelic Poly(ethylene glycol) Macromonomers. Preparation of Poly(ethylene glycol) Possessing a Methacryloyl Group at One End and a Formyl Group at the Other End, Macromolecules, 30, 6489,1997. 

Scheme 23.3 Chemoselective polymerization of a phenol derivative having a methacryloyl group by peroxidase catalyst.

Normally, a maaomonomer carries only a single oligomer chain. The combination of a terminal vinyl group with two polymeric chains has also been reported. In such an example, macromonomers consisting of a methacryloyl group as a polymerizable unit and two PS or poly(tert-butyl acrylate) (PtBA) chains were prepared in two steps as shown in Figure 3 (1) ATRP of styrene or tBA was initiated by a diinitiator, 1 -hydroxymethyl-1,1 -di [ (2-bromoisobutyryloxy)... 

Metabolic Delivery of Methacryloyl Groups into Carbohydrates.255... 

Confirmation of delivery of the methacryloyl groups to the cell surface was performed using the thiol-ene reaction. After 3 days of HL-60 cell cultivation in the presence of 5 mM ManM, the cells were rinsed three times with the cell culture medium. RPMI-1640 medium containing 2.5 wt% thiol-terminated 4-arm poly(ethylene glycol) (PEG4IOK-SH) and... 

This process may be advantageous for the functionalization of cell surfaces because the synthetic polymers are immobilized at the topmost surfaces of the cells. In addition, the methacryloyl group is the most desirable group for polymer synthesis and should be effective for the preparation of cell-based polymer materials. 

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