A living polymerization process is one that can produce polymers of predetermind molecular weight and a narrow molecular weight distribution containing one or more monomer sequences, the length and composition of which are controlled by stoichiometry of the polymerization reaction and degree of conversion. One such process is reversible addition-fragmentation-termination (RAFT). While compounds made by RAFT function effectively as chain transfer agents, they share one major disadvantage with the entire class of sulfur-based compounds: a characteristic disagreeable odor.
Anionic polymerization processes variously termed living, controlled, or immortal are used to synthesize polymers having a narrow molecular weight distribution and low polydispersity (1.5). These processes are so named because polymerization generally occurs by addition of monomer units to a constant number of growing polymer chains until all monomer has been consumed; if more monomer is added, polymerization resumes.
This technology relates to nanoparticles that are particularly beneficial in optical systems. The nanoparticles include phosphor-functionalized particles with an inorganic nanoparticle core, surface polymer brushes in the form of long and short-chain polymers bonded to the inorganic nanoparticle core, and organic phosphors bonded to the inorganic nanoparticle core or the short-chain polymers. Applications for this technology include LEDs, lighting devices, fixtures, efficient light conversion materials, etc.
Rensselaer researchers have developed a thermodynamically stable dispersion technology resulting in thick, transparent, high refractive index silicone nanocomposites that increase the light efficiency of LEDs and improve the emitted light color quality. The nanocomposites could also be processed as transparent bulk material with high filler loading, which is essential for optical, magnetic and biomedical applications.
This technology relates to synthesizing nanoparticles with multiple polymer assemblies attached. In one example, a first anchoring compound is attached to a nanoparticle, and a first group of monomers are polymerized on the first anchoring compound to form a first polymeric chain covalently bonded to the nanoparticle via the first anchoring compound. In another example, a first polymeric chain can be attached to the nanoparticle, where the first polymeric chain has been polymerized prior to attachment to the nanoparticle.
This technology relates to nanofilled polymeric materials with a tunable refractive index without increased scattering or loss. The tunability allows the creation of hybrid nanocomposites that combine the advantages of organic polymers (low weight, flexibility, good impact resistance, and excellent processability) and inorganic materials (high refractive index, good chemical resistance and high thermal stability).
Living polymerization is a method by which polymers having a narrow molecular weight distribution may be obtained. Block copolymers may also be synthesized using the method. Block copolymers may display improved mechanical andor chemical properties over corresponding random copolymers. One promising method for free radical polymerization with living characteristics is reversible addition-fragmentation chain transfer (RAFT) polymerization.