摘要:
Embodiments of the present invention include a material comprising a polymer having a modulus of elasticity less than 105 Pa and a material comprising a polymer having a modulus of elasticity of less than 5×104 Pa. Embodiments also include a material comprising a polymeric network and a multiplicity of side chains attached to the polymeric network. The multiplicity of side chains may have an average molecular weight below the critical molecular weight for entanglements. In certain embodiments it may be advantageous for the side branches to have a glass transition temperature below the use temperature of the material. The polymer network may comprise at least two monomers so that the polymer network is a copolymer. Embodiments of the present invention also include methods of forming a polymer network. Such as, for example, a method of preparing a polymer network comprising cross-linking a polymer, wherein the polymer comprises a multiplicity of side chains. The polymer may be at least one of a polymer brush, a polymer comb, and a nanocomposite material. An additional embodiment may include polymerizing macromonomers in the presence of a crosslinking agent. This embodiment may result in the forming a polymer network, wherein the polymer network comprises a multiplicity of branches attached to the polymer network, wherein the macromonomers may have a molecular weight less than the critical molecular weight for entanglements. Another embodiment of the method of forming a polymer network may comprising polymerizing monomers directly from a crosslinked polymer network. This method may result in forming a branched polymer network, wherein the polymer network comprises a multiplicity of branches attached to the polymer network.
摘要:
The invention generally relates to a method of inhibiting polymerization of vinyl aryl monomers, a process for increasing number average molecular weight of a polystyrene, and to an inhibitor composition useful therein.
摘要:
Methods for conducting controlled grafting-from radical polymerizations from biomolecules under conditions that are biologically compatible are described. The methods provide biomolecule-polymer conjugates with highly controlled structures and narrow polydispersities under aqueous reaction conditions and biological temperatures. Biomolecules, such as proteins and nucleotides can be conjugated to polymers with high levels of control.
摘要:
A polymer formed by controlled radical polymerization includes groups that can be modified after controlled radical polymerization to form a radical. The polymer can be the reaction product of a controlled radical polymerization of radically polymerizable monomers, wherein at least one of the radically polymerizable monomers includes at least one group that can be modified after the controlled radical polymerization to form a radical. A compound includes a first group that is stimulated upon application of energy to the molecule to tether the molecule to a surface or to another polymer chain and a second group comprising a controlled radical polymerization initiator functionality. A block copolymer includes at least a first segment to impart a predetermined functionality to a target surface and at least a second segment including functional groups to interact with the targeted surface to attach the block copolymer to the surface. The first segment can free of functional groups that interact with the surface to attach the block copolymer to the surface.
摘要:
The present invention relates to a polymerization inhibitor composition and a method of inhibiting polymerization of distillable monomers in liquid and evaporated/condensed phases with the polymerization inhibitor composition. The polymerization inhibitor composition is useful for inhibiting polymerization of the distillable monomers during manufacture, purification (e.g., distillation), handling, and storage thereof.
摘要:
A core-shell composite particle for incorporation into a composite wherein the composite has improved transparency is disclosed. The core-shell composite particle includes a core material having a first refractive index and a shell material having a second refractive index where the core-shell particle has an effective refractive index determined by the first refractive index and the second refractive index. The effective refractive index is substantially equal to the refractive index of the envisioned embedding medium. Methods of forming the core-shell particles are also disclosed.
摘要:
The invention is directed to a microemulsion polymerization comprising adding a polymerization catalyst precursor, such as a transition metal complex in the higher of two accessible oxidation states, an ATRP initiator, and an organic solvent to an aqueous solution to form an emulsion. Radically polymerizable monomers and a reducing agent may then be added to the emulsion. The reducing agent converts the catalyst precursor to a catalyst for polymerization of the first monomer from the initiator. In certain embodiments the organic solvent may comprise radically polymerizable monomers. The aqueous solution may comprise a surfactant. Further embodiments are directed to an ah initio polymerization process comprising adding a polymerization catalyst precursor; an ATRP initiator, and an organic solvent to an aqueous solution to form an emulsion, wherein the organic solvent comprises second radically polymerizable monomers, adding a reducing agent to convert the catalyst precursor to a catalyst for polymerization of the first radically polymerizable monomer from the initiator; and adding first radically polymerizable monomers to the emulsion.
摘要:
A polymerization process comprising initiating a first polymerization of monomers using an initiator functionalized with an ATRP initiating site, wherein the first polymerization is selected from the group of cationic polymerization, anionic polymerization, conventional free radical polymerization, metathesis, ring opening polymerization, cationic ring opening polymerization, and coordination polymerization to form a macroinitiator comprising an ATRP initiating site and further initiating an ATRP polymerization of radically polymerizable monomers using the macroinitiator comprising an ATRP initiating site. Novel block copolymers may be formed by the disclosed method.
摘要:
Improved processes for atom (or group) transfer radical polymerization (ATRP) and novel polymers have been developed and are described. In certain embodiments, novel copolymers comprising a least one polymeric branch or polymeric block with a predominantly alternating monomer sequence are described. Novel copolymers comprising a least one polymeric branch or polymeric block with a gradient monomer structure are described. Additionally, novel copolymers comprising a least one polymeric branch or polymeric block with a predominantly periodic monomer sequence are also described. Novel copolymers having a water soluble backbone and at least two hydrophobic polymeric branches grafted to the water soluble backbone are also described.
摘要:
A new polymerization process (atom transfer radical polymerization, or ATRP) based on a redox reaction between a transition metal (e.g., Cu(I)/Cu(II), provides "living" or controlled radical polymerization of styrene, (meth)acrylates, and other radically polymerizable monomers. Using various simple organic halides as model halogen atom transfer precursors (initiators) and transition metal complexes as a model halogen atom transfer promoters (catalysts), a "living" radical polymerization affords (co)polymers having the predetermined number average molecular weight by .DELTA.�M!/�I!.sub.0 (up to M.sub.n >10.sup.5) and a surprisingly narrow molecular weight distribution (M.sub.w /M.sub.n), as low as 1.15. The participation of free radical intermediates in ATRP is supported by end-group analysis and stereochemistry of the polymerization. In addition, polymers with various topologies (e.g., block, random, star, graft, hyperbranched, dendritic end-functional and in-chain functional copolymers �for example, of styrene and methyl (meth)acrylate!) have been synthesized using the present process. The Polymeric products encompassed by the present invention can be widely used as plastics, elastomers, adhesives, emulsifiers, thermoplastic elastomers, etc.