310 results about "P-Hydroquinone" patented technology

The present invention discloses the apparatus and method of separating and purifying phenol, catechol, hydroquinone and tar in water solution. The apparatus includes a dewatering distillation tower with entry end, a first phenol eliminating distillation tower, a second phenol eliminating distillation tower, a tar eliminating distillation tower, a deep distilling caldron, and a product distillation tower. The separating process includes the following steps: feeding the materials successively into the apparatus for rectification separating, and exhausting catechol and p-benzenediol separately in the top and the bottom of the product distillation tower. Owing to the continuous five tower vacuum distillation and high efficiency packing tower technology, the present invention has the features of low phenol content, low operation temperature, etc.

The invention discloses a low-cost polyester polycarboxylic acid water reducer, and relates to a building material. The low-cost polyester polycarboxylic acid water reducer is prepared from the following steps: an esterification reaction: conducting an esterification reaction on polyethylene glycol and methacrylic acid under effects of an inhibitor hydroquinone and a catalyst p-toluene sulphonic acid to generate esterification macromonomer polyethylene glycol methacrylate and water, wherein silica gel is used as an absorbent in the reaction to absorb water generated in the esterification reaction to proceed the reaction, and stopping the reaction when esterification rate reaches 40-60%; and a polymerization graft reaction: conducting isothermal reaction on the esterification macromonomer polyethylene glycol methacrylate with mixed monomer MAA, AM and SMAS in the presence of a chain transfer agent thioglycolic acid, an initiator ammonium persulfate and an initiating assistant hydrogen peroxide, cooling to room temperature after the reaction, and adding NaOH to adjust a pH value to 7. Compared with the prior art, the low-cost polyester polycarboxylic acid water reducer protected by the invention has advantages of low cost and good water reducing performance.

An acrylic ester polymer and its synthesis are disclosed. The process is carried out by heat polymerizing for mixture of thermal initiator benzoyl peroxide and acrylic ester under agitation and nitrogen protection to obtain acrylic ester polymer, adding into acrylic acid, taking tosylate as catalyst and hydroquinone as inhibitor, reacting at 100-110 degree, removing water, decompressing, and removing solvent and inactive raw material to obtain final product. It can be used to machine building material cyanamide paper, and improve coating and substrate performances and adhesion.

A method for cultivating Monarda fistulosa for production of thymoquinone includes planting seeds at rates between about 2.5 and about 5 pounds per acre, preferably about 4 pounds per acre. The heavy rate of planting produces plants bearing oil without weed contamination and reduces herbicide use due to production of natural herbicides by the monarda plants. Seeding and mowing the first season, and harvesting in seasons thereafter reduce costs. The method results in increased production of essential oils including thymoquinone and thymohydroquinone at levels up to about 40% or more of recovered oils, and which may be distilled from the plant.

The invention discloses a method for synthesizing R-(+)-2-(4-hydroxyphenoxy)propionic acid through gas phase catalysis, and belongs to the field of organic synthesis. Hydroquinone and D-lactic acid are used as raw materials, and nitrogen is used as a carrier gas. The hydroquinone and the D-lactic acid are completely gasified and then enter a fixed bed reactor, and the R-(+)-2-(4-hydroxyphenoxy)propionic acid is continuously synthesized in a gas phase under the catalysis of a supported heteropolyacid catalyst. The method has the advantages of mild reaction conditions, simple reaction process, high effective conversion rate of hydroquinone and high selectivity of the R-(+)-2-(4-hydroxyphenoxy) propionic acid, and is completely suitable for industrial production, and the self-made supported heteropolyacid solid catalyst has excellent catalytic activity, strong acidity, good stability and no pollution to the environment, and is a green catalyst.

The invention relates to the field of adhesives, in particular to an anaerobic adhesive and a preparation method of the anaerobic adhesive. The anaerobic adhesive comprises 40-100 parts of modified methacrylic acid, 0.8-5 parts of an initiator, 1-4 parts of an accelerant and 0.5-2 parts of an accelerant aid. According to the anaerobic adhesive, polyurethane modified epoxy resin is adopted to modify methacrylic acid, and the preparation method specifically comprises the following steps: adding the polyurethane modified epoxy resin into a reaction kettle, heating to be 60-65 DEG C, adding hydroquinone, adding methacrylic acid when hydroquinone is completely dissolved, continuously heating to be 70-80 DEG C, adding triethylamine, uniformly mixing, heating to be 80-85 DEG C, reacting for 1-3 hours, further heating to be 98-100 DEG C, and reacting for 2-4 hours, so as to obtain the modified methacrylic acid. The anaerobic adhesive provided by the invention is good in toughness and low-temperature resistance, and is also relatively high in tension strength, shearing resistance and impact resistance.

An improved process for production and novel physical forms of butylated hydroxyanisole (BHA) is described wherein tertiary butyl hydroquinone (TBHQ) reacts within a range of about 30 to 50 DEG C with stoichiometrically slight excess of dimethyl sulphate and sodium hydroxide, the sodium hydroxide being added stoichiometrially in slight excess of dimethyl sulphate. Major portion of BHA formed in this reaction was recovered in a crystalline form in which 3-t-butyl-4-hydroxyanisole (3 isomer) is at least at about 99% level, usually at about 99.5% or more, and TBHQ at 100 ppm or less. BHA remaining in mother liquor after crystallization was recovered by distillation and had same purity as the crystalline BHA. The crystalline form was prepared as low density as well as high density form and further could be converted into compressed forms including flakes, tablets and the like.

The invention relates to a sanding-free unsaturated polyester primer applicable to melamine substrates and a preparation method thereof. The sanding-free unsaturated polyester primer applicable to melamine substrates is prepared by mixing the following components in parts by weight: 100 parts of main paint, 1.0-1.2 parts of initiator and 1.2-1.4 parts of accelerator. The main paint is prepared from an unsaturated polyester resin, a dispersing agent, hydroquinone, a defoaming agent, a leveling agent, rutile titanium white, ground calcium carbonate, talcum powder, gas-phase silicon dioxide, zinc stearate, an adhesion enhancer and styrene; the accelerator is cobalt naphthenate; and the initiator is methylethyl ketone peroxide. The sanding-free unsaturated polyester primer applicable to melamine substrates can be directly sprayed without sanding the substrate when being applied to the melamine substrate, and has excellent adhesive force and fullness after being sprayed.

The invention provides a method for improving the molecular weight of a thermotropic liquid crystal polymer. According to the method, in the process of preparing the thermotropic liquid crystal polymer by using p-hydroxybenzoic acid / p-acetoxybenzoic acid, 6-hydroxy-2-naphthoic acid / 6-acetoxy-2-naphthoic acid, hydroquinone / hydroquinone diacetate and terephthalic acid, the molar ratio of the hydroquinone / hydroquinone diacetate to the terephthalic acid is controlled to be (1.005-1.025): 1. The molecular weight of the polymer product is controlled by controlling the addition amount of certain monomers, so that the polymerization time can be greatly shortened and the production efficiency is improved.

The invention discloses an interventional anti-infective water-based adhesive which comprises the following components in parts by weight: 100 parts of n-octyl a-cyanoacrylate, 10-15 parts of polymethacrylate, 4-10 parts of tetracycline, 2-6 parts of secnidazole, 0.2-0.5 part of hydroquinone and 0.05-0.2 part of sulfur dioxide. The interventional anti-infective water-based adhesive disclosed by the invention enables the human body tissues to be easy for binding in an anaerobic and solvent environment, has counter force against anaerobes, can effectively relieve the infection of the human body tissues in or after operation, and has the function of diminishing inflammation, thereby ensuring the binding effect of the human body tissues.