Macromers copolymers

Earlier, successful attempts at physically crosslinking acrylic PSAs have been disclosed in the work of Husman et al. [98], Mancinelli and colleagues [99,100] and others. Instead of making ABA type structures, these authors studied and developed the use of high macromers in acrylic copolymers. Macromers are... 

Liu B, Lewis AK, Shen W (2009) Physical hydrogels photo-cross-linked from self- assembled macromers for potential use in tissue engineering. Biomacromolecules 10 3182-3187 Vandermeulen GWM, Tziatzios C, Duncan R et al (2005) Peg-based hybrid block copolymers containing alpha-helical coiled coil peptide sequences control of self- assembly and preliminary biological evaluation. Macromolecules 38 761-769... 

Block copolymers are also produced using such macromers. Again, the various units of the polymer can be designed to act as needed with hard or/soft, or hydrophilic or hydrophobic, or other combinations. In addition, these macromers generally have two active functional groups that allow polymerization to occur. 

The engineering of lignin-based macromers with propylene oxide to target specifications appears as a useful technique for formulating components for block copolymers and segmented thermosets. 

Acrylated lignin derivatives are viewed as a new and promising class of functional macromers from lignin useful for the formulation of block and segmented copolymers. 

The very sharp peak on the left is the MACROMER and the curves on the right are the growing copolymer peaks. One sees that by the time 55% of the vinyl chloride conversion is completed that the MACROMER is virtually completely copolymerized and that its peak has almost disappeared. This at least indicates the existence of a functional MACROMER . 

It was demonstrated that MACROMER will copolymerize with conventional monomers in a predictable manner as determined by the relative reactivity ratios. The copolymer equation ... 

Some experimental data that were obtained through a series of polymerization studies with a methacrylate-terminated MACROMER with vinyl chloride are shown in Figure 12. The Alfrey-Goldfinger equation was used to calculate the copolymer composition for comparison to the actual copolymer composition as estimated from GPC analysis. A reasonably close agreement was achieved of the actual and the theoretical copolymer compositions, which indicates that the r values are in the region of r2 = 10 and r2 = 0.1. 

Figure 14. Stress-strain curves for 1 1 ethyl acrylate butyl acrylate copolymers with S16MA MACROMER at 30%, 40%, and 50% MACROMER contents.

Functionally terminal polymers are valuable material intermediates. The di- and polyfunctional varieties (telechelic polymers) have found theoretical (e.g., model network) and commercial (e.g., liquid rubber) applications (1, ). On the other hand, macromolecules with a functional group at one chain end (semitelechelic polymers) have been used to prepare novel macromolecular monomers (Macromers ), as well as block and graft copolymers ( -8). 

FBZ precursor and can therefore be attributed to the segregated PFPE moiety. This kind of behavior is quite general for copolymers containing PFPE macromers and also in the Z1072 and Z1073 resins themselves. The driving force is the relevant difference in solubility parameters between fluorinated and nonfluorinated macromers, since the cohesive energy density (CED) of the perfluorocopolyethers is one of the smallest known. ... 

Peptidyl macromers, in which a vinyl group was introduced at the N-terminus, were synthesized by solid-phase methodology. More specifically, the peptide H-Gly-Gly-Gly-Arg-Gly-Asp-Ser-Pro-OH had acrylic acid coupled to the N-terminus. The peptidyl macromer was cleaved and deprotected by standard methods. Copolymers of styrene with these peptidyl macromers were prepared by radical copolymerization in DMF soln. Cast films were prepared from a CHC13 soln of copolymers. 

The cyclic tin alkoxides have the additional advantage of offering a convenient synthetic pathway for the synthesis of macromers, triblock, and multiblock copolymers [81,82]. Macromers from l-LA [83],e-CL [84], and l,5-dioxepan-2-one (DXO) [85] have been synthesized as well as triblock poly(L-LA-b-DXO-b-L-LA) [86] and multiblock copoly(ether-ester) from poly(THF) and e-CL [87]. The polymerization proceeds by ring expansion and the cyclic structure is preserved until the polymerization is quenched by precipitation. 

The preparation of prepolymers [111] or macromers with functional end groups, so called telechelic polymers, is another approach to structurally unconventional architecture. The functional end groups are introduced either by functional initiation or end-capping of living polymers, or by a combination of the two. In this way, monomers that are not able to copolymerize can be incorporated in a copolymer. Telechelic prepolymers can be linked together using chain extenders such as diisocyanates [112]. In this process, it is essential that the structure and end groups of the prepolymers can be quantitatively and qualitatively controlled [113]. 

The above thermal analysis studies demonstrated the enhanced thermal stability of POSS materials, and suggested that there is potential to improve the flammability properties of polymers when compounded with these macromers. In a typical example of their application as flame retardants, a U.S. patent39 described the use of preceramic materials, namely, polycarbosilanes (PCS), polysilanes (PS), polysilsesquioxane (PSS) resins, and POSS (structures are shown in Figure 8.6) to improve the flammability properties of thermoplastic polymers such as, polypropylene and thermoplastic elastomers such as Kraton (polystyrene-polybutadiene-polystyrene, SBS) and Pebax (polyether block-polyamide copolymer). 

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