Matrix-forming monomer

Zn(II) was employed as a print molecule because of its strong interaction with the bifunctional monomer, DDDPA. Divinylbenzene, L-glutamic acid dioleylester ribitol and toluene were used as matrix-forming monomer, emulsion stabiliser and diluent, respectively. After polymerisation, the print molecules were removed from the resin, upon which selective recognition sites were formed. The schematic illustration of surface template polymerisation with DDDPA is shown in Scheme 9.8. The Zn(II)-imprinted resins were ground into particles, whose volume-averaged diameters were ca. 40 pm. The yield was ca. 80%. 

Benoit et al. [11-12] and Akcasu et al. [13-15] have extended de Gennes formula to describe multicomponent polymer systems. Their results are reproduced in Appendix A in a matrix form (following Akcasu [13-15]). Consider a number of components (noted A, B, etc.) with degrees of polymerization NA, etc., volume fractions A, etc., monomer volumes vA, etc. Some of these components could be block copolymers. Having one of the components (called matrix component) as a homopolymer simplifies the calculations. The main result is ... 

Following the standard RPA formalism, we define externally applied (weakly perturbing) potentials U (U is an n-component vector that can depend on Q but not on monomer orientations) and inter-segment potentials W (u, u ) (nxn matrix) where u and u represent the directions of two test segments. Within the mean field approach, the RPA equations give the mean response of the averaged densities (

is an n-vector) in terms of the response functions for the bare system X0(Q, u,u ) (nxn matrix) and for the interacting system X(Q, u, u ). In this matrix notation approach, bold face characters are used to represent n-vectors, nxn matrices as well as three-dimensional cartesian vectors such as direction u. The RPA equations in the matrix form are ... 

A polymer with short isotactic sequences was formed. During polymerization of the same monomer in solution, syndiotactic addition is preferred [37]. The counter ions of matrix and monomer are bound by electrostatic forces. These... 

Although the dynamically vulcanized blends such as EPDM/PP (Santoprene ) and NBR/PP (Geolast ) have sometimes been referred in the literature as semi-IPNs, we considered them as blends of crosslinked elastomer dispersions in a thermoplastic matrix and as such treated them under the elastomer blends. There is yet another class of thermoplastic/thermoset blend system in which a minor amount of the crosslinkable monomer(s) is allowed to polymerize in the thermoplastic matrix forming a loose network. 

The conversion from monomer to polymer in the crystal proceeds via a diffusionless phase transition to form perfect polymer single crystals with the lattice parameters close to those of the original monomer crystals. During the course of the polymerization, the polymer chains and the monomer matrix form a homogeneous solid solution without any nucleation of the product phases, thus neither destruction nor fibrillation can be observed in the resultant polymer single crystals. Solid state polymerization of conjugated diynes is... 

FIGURE 54.10 SEM image of a polymer matrix formed by infusing the monomers into a coUoidal crystal, polymerizing the monomers, and then etching away the crystals. The nanopores between the cavities are the result of incomplete wetting of the colloids at their junctions. (Reprinted from Jiang, P., et al., J. Am. Chetn. Soc., 121, 11630, 1999. With permission.)... 

The rate matrix for multicomponent copolymerization can thus also be expressed in terms of the homopolymerization propagation rate constants of the n monomers, and reactivity ratios as defined in a similar manner to Equation (10.7). The set of copolymerization rate equations given by Equation (10.30) can be given in matrix form as follows ... 

The ability of a new biodegradable polymer, polyurethane triethylene glycol 1,6-hexa-methylene diisocyanate PU(TEG-HMDI), to act as matrix-forming polymer for controlled release tablets has been studied and its percolation threshold in a matrix system has been estimated [112]. The hydrophilic polyurethane PU(TEG-HMDI) was successfully synthesized by reaction of 1,6-hexamethylene diisocyanate (HMDI) and triethylene glycol (TEG) (Scheme 4.1). The diol monomer (TEG) was chosen to enhance the hydrophilic nature and swelling properties of the new material. These properties contribute to the degradability of the polyurethane. 

Investigations have indicated [26, 71] that not only relatively e q)ensive bifimctional network-forming monomers, but also quite accessible monomers (styrene, for example) which give a linear polymer with high value of d may be used as a matrix, if a network structure is formed in it by the use of cross-linking agents [26, 72]. 

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