Crosslinked poly diacrylate

Vollmert presented 31 examples of multipolymer compositions, some of which were IPNs, (see Table 8.1). In example 20, a crosslinked poly(n-butyl acrylate) makes up network I. Poly(n-butyl acrylate-co-acrylonitrile) crosslinked with 1,4-butane-diol diacrylate makes up network II on a separate latex. A linear poly(styrene-co-acrylonitrile) latex makes up polymer III for a third latex. The three latexes are blended to form an impact-resistant polystyrene. This particular product, however, is not an IPN, because the two crosslinked latexes were polymerized and crosslinked separately and then mechanically blended together. 

Kalakkunnath, S., Kalika, D. S., Lin, H., and Freeman, B. D. (2(X)5). Segmental relaxation characteristics of crosslinked poly(ethylene oxide) copolymer networks. Macromolecules 38, 9679. Kalakkurmath, S., Kalika, D. S., Lin, H., and Freeman, B. D. (2(X)6). Viscoelastic characteristics of U.V. polymerized poly(ethylene glycol) diacrylate networks with varying extents of ciosslinking. 

Lin, H., and Freeman, B. D. (2005a). Gas and vapor solubility in crosslinked poly(ethylene glycol diacrylate). Macromolecules 38, 8394. 

Crosslinked polymer networks formed from multifunctional acrylates are completely insoluble. Consequently, solid-state nuclear magnetic resonance (NMR) spectroscopy becomes an attractive method to determine the degree of crosslinking of such polymers (1-4). Solid-state NMR spectroscopy has been used to study the homopolymerization kinetics of various diacrylates and to distinguish between constrained and unconstrained, or unreacted double bonds in polymers (5,6). Solid-state NMR techniques can also be used to determine the domain sizes of different polymer phases and to determine the presence of microgels within a poly multiacrylate sample (7). The results of solid-state NMR experiments have also been correlated to dynamic mechanical analysis measurements of the glass transition (1,8,9) of various polydiacrylates. 

He et al. (2) prepared a hydrolyzably crosslinked biodegradable network consisting of poly(propylene fumarate) crosslinked with the diacrylate derivative of poly(propylene fumarate), (I). 

Figure 10.3 Mean molecular mass between chemical crosslinks and trapped chain entanglements Mc+e in a cured mixture of a poly(ethylene glycol) diacrylate (PEGDA) and 2-ethylhexyl acrylate (EHA) as a function of the EHA content [52]. Mc+e values were determined from (1/T2s)max and the plateau modulus (see Figure 10.2). A substantial difference in Mc+e value, as determined by these two methods at low crosslink density, is caused by the effect of network defects which decrease volume average network density determined by DMA (see Section 10.3). The molecular mass of PEGDA (Mn = 700 g/mol) is indicated by an arrow. The molecular mass of network chains in cured PEGDA is about three times smaller than that of the initial monomer. The molecular origin of this difference is discussed in Section 10.3...

Sawhney and co-workers prepared a series of PEC-co-poly(a-hydroxy acid) diacrylate macromers and investigated their photopolymerization into crosslinked bioerodible hydrogels. Certain types of these hydrogels were evaluated for use in preventing postsurgical adhesion and vascular restenosis. ... 

He, S., Timmer, M. D., Yaszemski, M. J., Yasko, A. W., Engel, P. S. Mikos, A. G. (2001) Synthesis of biodegradable poly(propylene fumarate) networks with poly(propylene fumarate)-diacrylate macromers as crosslinking agents and characterization of their degradation products. Polymer, 42, 1251-1260. 

Timmer MD, Ambrose CG, Mikos AG. In vitro degradation of polymeric networks of poly(propylene fumarate) and the crosslinking macromer poly(propylene fumarate)-diacrylate. Biomaterials 2003 24(4) 571-577. 

Poly(Propylene Fumarate) (PPF) is a linear, unsaturated, hydrophobic polyester (Structure 12) containing hydrolyzable ester bonds along its backbone. PPF is highly viscous at room temperature and is soluble in chloroform, methylene chloride, tetrahydrofuran, acetone, alcohol, and ethyl acetate [66]. The double bonds of PPF can form chemical crosslinks with various monomers, such as W-vinyl pyrrolidone, poly(ethylene glycol)-dimethacrylate, PPF-diacrylate (PPF-DA), and diethyl fumarate [67,68]. The choice of monomer and radical initiator directly influence the degradative and mechanical properties of the crosslinked polymer. Once crosslinked, PPF forms a solid material with mechanical properties suitable for a range of bone engineering applications. 

Poly(methyl acrylate) (PMA) may be used as start material for production of shape-memory material [lOWl]. The addition of poly(ethylene glycol) diacrylate (PEGDA) assists crosslinking process. The insoluble content formed in EB-irradiated PMA increases sharply even at low doses (Table 37) because polymer matrix provides radicals at a yield of 0.77 and PEGDA plays the role of sensitizer. 

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