Method for preparing hydrophobic core material microcapsule by taking petroleum resin as raw materials of wall material

Abstract

The invention discloses a method for preparing a hydrophobic core material microcapsule by taking petroleum resin as raw materials of a wall material. The microcapsule is obtained by free radical polymerization of a hydrophobic core material and C9 petroleum resin which are used as the raw materials of the wall material. The preparation method of the microcapsule comprises the following steps of firstly, dissolving the C9 petroleum resin into at least one kind of monomer, and adding an oil-soluble initiator and performing prepolymerization at the temperature of 20 to 150DEG C for 10 to 60 minutes to obtain a C9 petroleum resin prepolymerization solution; secondly, adding a liquid hydrophobic core material or the hydrophobic core material and a cross-linking agent in the C9 petroleum resin prepolymerization solution to obtain an oil phase; thirdly, dispersing the oil phase into a water solution containing a dispersing agent by a mechanical method, and continuously performing polymerization reaction at the temperature of 20 to 150DEG C for 1 to 8 hours; fourthly, after the reaction is ended, filtering, washing and drying to obtain the microcapsule. The wall material of the obtained microcapsule is formed by reacting 10 to 50 weight percent of C9 petroleum resin, 40 to 80 weight percent of monomer and 0 to 20 weight percent of cross-linking agent.

Description

technical field [0001] The invention belongs to the field of fine chemicals, and in particular relates to a method for preparing microcapsules by using petroleum resin as a wall material raw material, in particular to a method for preparing hydrophobic core material microcapsules using C9 petroleum resin as a wall material raw material Background technique [0002] Microcapsule technology is a technology that uses shell-forming materials to wrap solids and liquids to form tiny particles with a particle size in the micron range. Microcapsules can protect substances from environmental influences, reduce their toxicity, mask their bad taste, control the release of core materials, increase the storage period, change the state of substances to facilitate storage and transportation, change physical properties to make incompatible ingredients evenly mixed, prevent The shape of the product changes when the solid-liquid phase changes. These functions make microcapsule technology wide...

AI Technical Summary

Problems solved by technology

[0011] In these methods, the monomers and crosslinking agents used contain at least one unsaturated carbon-carbon double bond. In terms of chemical properties, these substances are chemically unstable, and the carbon-carbon double bonds contained in the molecules are prone to free radical polymerization. Reaction, which is both an advantage and a disadvantage. The advantage is that this structural feature is the basis for these substances to be used for polymerization. The disadvantage is that because it is easy to polymerize, the required monomer or crosslinking agent is separated from the mixture during production. Generally, it is necessary to add a polymerization inhibitor, and it is also necessary to add a polymerization inhibitor when preparing a cross-linking agent. agent to prevent the polymerization of these active monomers or crosslinking agents during storage and transportation, because the efficiency of the polymerization inhibitor is high, and the dosage is generally small, such as the use of more polymerization inhibitor 4-methoxyphenol (CAS No.: 150-76-5), its concentration is generally not less than 10ppm (parts per million, means one part per million), because the storage period of the monomer added with 10ppm is generally 6 months, in order to extend the storage period, it is necessary to Increase the amount, up to 60ppm, the nature of the cross-linking agent is more active, the amount of polymerization inhibitor is larger, before the user uses, the polymerization inhibitor must be removed, the general method of removing the polymerization inhibitor is to use 5% hydroxide Wash with sodium solution, then separate liquid, then add sodium oxide solution to wash the oil phase after liquid separation, then separate liquid, repeat several times, because the concentration of sodium hydroxide solution is very small, thus produce a large amount of waste water, if directly discharged, pollution Environment, if the wastewater is treated, it will add a lot of money. As a common sense, the lower the concentration of the substance, the higher the purification cost. The cost of removing a small amount of substances increases geometrically with the decrease of the concentration of impurities.

Another disadvantage is that whether it is a monomer used as a polymerization raw material or a cross-linking agent, the chemical properties are very active, and the production cost is relatively high. Although its usage is small, it accounts for a considerable proportion of the production cost. When the product performance is similar, the price factor is often the decisive factor. For example, microcapsules used for building energy saving can save energy by more than 30% when used together with other energy-saving means. , the energy-saving effect is obvious, but it has been unable to be used on a large scale because the price is too high and the market does not accept it. Microcapsules used for energy storage, thermal protection or thermal functional fluids, reversible thermochromic microcapsules and other hydrophobic core material microcapsules The production of capsules also needs to reduce the production cost to facilitate the use and promotion. Therefore, it is necessary to look for raw materials with suitable chemical properties and low prices to partially or completely replace the monomers and cross-linking agents for the preparation of microcapsules by free radical polymerization, no matter in terms of energy saving and emission reduction , or from the perspective of reducing production costs and enhancing product market competitiveness, it is undoubtedly of practical significance

Images