摘要:
The present invention is directed to the preparation of photoresist polymers via living free radical polymerization techniques. Sterically bulky ester monomers are utilized as the polymerization components. Use of chain transfer agents is included in polymerization processing conditions. Cleavage of polymer terminal end groups that include a heteroatom are described.
摘要:
Control agents that have a nitrogen-nitrogen bond in a cyclic ring covalently bonded to a thiocarbonyl moiety are provided for living-type free radical polymerization without a bimodal molecular weight distribution at high monomer conversions. These control agents provide superior properties for the production of block polymers having narrow molecular weight distributions.
摘要:
This invention provides a method for removing unwanted groups from a chain end of a polymer and replacing them with a more desirable group. In one aspect, the invention provides a method of free radical polymerization. The method includes forming a mixture of one or more monomers, at least one free radical source and a chain transfer agent, wherein the chain transfer agent includes a thiocarbonylthio group, and subjecting the mixture to polymerization conditions. The resulting polymer, which has one or more thiocarbonylthio end groups, is then contacted with a free radical source and optionally an addition fragmentation agent or a monomer with little or no homopolymerizability under cleavage reaction conditions. The free radical source is activated to generate radicals, and at least 50% of the thio end groups of the polymer are replaced with a group of interest other than hydrogen.
摘要:
Control agents that have a nitrogen-nitrogen bond covalently bonded to a thiocarbonyl moiety are provided for living-type free radical polymerization of a wide variety of monomers. These control agents provide superior properties for control of the polymerization and/or the properties of the polymers obtained and/or the monomers that may be polymerized. In some embodiments, a bulky group is pendant off the activated thiocarbonyl portion of the control agents. Multifunctional control agents provide the opportunity for a variety of structurally unique polymers, including block copolymers, stars and hyper-branched polymers.
摘要:
Sensors for determining the presence and concentration of bio-molecules in a biological sample are provided in the form of polymer brushes, which comprise a substrate having a surface that is modified with a water-dispersible or water-soluble polymer segment having functional groups that bind probes. The method of synthesis of such sensors preferably includes use of controlled free radical polymerization techniques which allows for controlled architecture polymers to modify the surface of the substrate. In this manner functional groups in the polymer chain are removed from the surface, which allows for solution chemistry to be more realistically reproduced with the benefits of a solid bound probe.
摘要:
Control agents that have a nitrogen-nitrogen bond in a cyclic ring covalently bonded to a thiocarbonyl moiety are provided for living-type free radical polymerization without a bimodal molecular weight distribution at high monomer conversions. These control agents provide superior properties for the production of block polymers having narrow molecular weight distributions.
摘要:
Sensors for determining the presence and concentration of bio-molecules in a biological sample are provided in the form of polymer brushes, which comprise a substrate having a surface that is modified with a water-dispersible or water-soluble polymer segment having functional groups that bind probes. The method of synthesis of such sensors preferably includes use of controlled free radical polymerization techniques which allows for controlled architecture polymers to modify the surface of the substrate. In this manner functional groups in the polymer chain are removed from the surface, which allows for solution chemistry to be more realistically reproduced with the benefits of a solid bound probe.