- Preparation of polymer latex particles carrying salt-responsive fluorescent graft chains
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We prepared the novel fluorescent polymer latex particles which can change their fluorescence intensity in response to the increasing NaCl concentration in water. Core polymer latex particles were synthesized by emulsifier-free emulsion polymerization of styrene and 2-(2-chloroisobutyroyloxy)ethyl methacrylate. Hydrophilic polymer chains containing epoxy groups were grafted from the core particles by surface-initiated atom transfer radical copolymerization of methoxy polyethyleneglycol methacrylate (MEOxMA, x = 4 or 9) and glycidyl methacrylate in aqueous media. After azidation of epoxy groups in graft chains, a water-soluble fluorescent dansyl derivative was successfully coupled with the graft chains by copper-catalyzed azide-alkyne cycloaddition in aqueous media. The wavelength of maximum fluorescence intensity of polymer particles carrying graft chains with longer PEG side chains (x = 9) was slightly blue-shifted (7 nm) and the fluorescence intensity increased (1.35 times) with an increase in NaCl concentration as opposed to polymer particles with shorter PEG chains (x = 4).
- Kasuya, Masakatsu,Taniguchi, Tatsuo,Kohri, Michinari,Kishikawa, Keiki,Nakahira, Takayuki
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- Biotin functionalized poly(sulfonic acid)s for bioconjugation: In situ binding monitoring by QCM-D
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We describe the synthesis of biotin end functionalized poly(sulfonic acid)s via living radical polymerization (LRP) for conjugation to Avidin. Quartz crystal microbalance (QCM-D) and competitive binding studies were used to confirm this conjugation. A biotin initiator for copper-mediated LRP was used to provide acrylamide and methacrylate based polymers with the functional end group. This investigation revealed that 2-acrylamido-2-methyl-1-propanesulfonic acid was not a suitable monomer in its acid form but was successfully used in its sodium salt form. A second monomer, 3-sulfopropylmethacrylate as the potassium salt was also studied and both monomers produced polymers with polydispersities 1.3 and 1.4, respectively. Evolution of molecular weight with respect to time indicated that the polymerization of the acrylamide polymer is controlled. Quartz crystal microbalance with dissipation monitoring was used to confirm that the biotinylated polymers were able to bind to Avidin in situ. The gold surface of a quartz crystal was chemically modified resulting in a stable monolayer of Avidin; the biotinylated polymers were passed over the functionalized surface and their grafting ability was examined. A competitive binding evaluation was undertaken with 2-(4-hydroxyphenylazo)benzoic acid (HABA) dye to provide visual verification of conjugation.
- Slavin, Stacy,De Cuendias, Anne,Ladmiral,Haddleton, David M.
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- Preparing method of photoinitiator 2-methyl-2-hydroxy-1-phenylacetone
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The invention discloses a preparing method of a photoinitiator 2-methyl-2-hydroxy-1-phenylacetone. The preparing method comprises the steps of conducting acylation reaction on isobutyric acid and phosphorus trichloride, after the reaction is completed, introducing hydrogen chloride gas to make the intermediate state reaction complete, obtaining 2-chloride-2-methyl propionylchloride through chlorination reaction, conducting Friedel-Crafts reaction with benzene in the presence of a catalyst to obtain 2-chloride-2-methyl-1-phenylpropane-1-ketone, and finally after alkaline hydrolysis, washing anddistillation, obtaining the photoinitiator 1173. According to the preparing method, hydrogen chloride is introduced into the acylation step, so that the reaction yield is increased, and byproduct odors are reduced; meanwhile, chlorination reaction of a conventional technology is conducted one step in advance, the production cost of the conventional technology is reduced, and thus the product hasmarket competitiveness.
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Page/Page column 4-6
(2019/04/30)
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- Synthetic method of free-radical photoinitiator
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The invention discloses a synthetic method of a free-radical photoinitiator. The synthetic method is characterized by comprising the following steps: (1) under the action of aluminium trichloride, methyl phenyl sulfide is adopted as a raw material and generates Friedel-Crafts acylation reaction with 2-chloroisobutyryl chloride to prepare an intermediate A with a structure shown in a formula (I); (2) under the action of alkaline, the intermediate A carries out ring-closure reaction to prepare an intermediate B with a structure shown in a formula (II); (3) the intermediate B and morpholine carryout ring-opening reaction to obtain a target product with a structure shown in a formula (III), namely the free-radical photoinitiator. The synthetic method disclosed by the invention has the beneficial effects that the photoinitiator is synthesized by the steps of adopting the 2-chloroisobutyryl chloride and methyl phenyl sulfide to carry out Friedel-Crafts acylation reaction, then carrying outcyclization and ring opening and the like, the obtained product contains fewer impurities, the yield is high, the process route is convenient in operation, and generates less three wastes (waste water, waste solid and waste air) so as to be more environment-friendly.
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Paragraph 0043; 0045; 0046; 0047; 0056; 0058; 0067; 0069
(2018/07/30)
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- METHOD FOR PRODUCING UNSATURATED ACID AND/OR UNSATURATED ACID ESTER
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The present invention relates to a method for producing an unsaturated acid and/or an unsaturated acid ester, containing a process A of reacting a compound (1) represented by the following formula (1) at a temperature of 0° C. to 350° C. in the presence of a Br?nsted acid catalyst and/or a Lewis acid catalyst, to prepare a compound (2) represented by the following formula (2); in which each of R1, R2 and R4 independently represents a hydrogen atom, a deuterium atom or an alkyl group; each of R3 and R5 independently represents a hydrogen atom or a deuterium atom; R6 represents a hydrogen atom, a deuterium atom, or an alkyl group or an aryl group; and X represents a chlorine atom, a fluorine atom, a bromine atom, or an iodine atom.
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Paragraph 0097-0099
(2015/07/02)
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- Asymmetric auto-tandem catalysis with a planar-chiral ruthenium complex: Sequential allylic amidation and atom-transfer radical cyclization
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Ru does it all: A novel example of an asymmetric auto-tandem reaction catalyzed by a planar-chiral cyclopentadienyl-ruthenium complex is described. The reaction of allylic chloride with α-haloamides provides synthetically useful, diastereomerically and enantiomerically enriched γ-lactams with multiple stereogenic centers through one-pot sequential allylic amidation/atom-transfer radical cyclization. PG=protecting group. Copyright
- Kanbayashi, Naoya,Takenaka, Kazuhiro,Okamura, Taka-Aki,Onitsuka, Kiyotaka
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supporting information
p. 4897 - 4901
(2013/06/05)
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- Photosensitive hydroxyalkylphenones
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Compounds of the formula STR1 wherein R1 is hydrogen, chlorine, phenyl, dialkylamino of 2-4 carbon atoms or alkyl or alkoxy each of up to 18 carbon atoms; R2 is hydrogen, chlorine, bromine or alkyl or alkoxy each of up to 4 carbon atoms; R3 and R4, which can be the same or different, each is hydrogen or alkyl of up to 6 carbon atoms; R5 is hydrogen or alkyl or alkanoyl each of up to 4 carbon atoms; and R6 is hydrogen or methyl, with the proviso that not all of R1 to R6 simultaneously are hydrogen, are effective photosensitizers, especially for photopolymerization of unsaturated compounds and for hardening of printing dyes.
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