Forming method of ultra-low viscosity polyvinyl alcohol solid

A molding method and technology of polyvinyl alcohol, applied in the field of polyvinyl alcohol, can solve the problems of low product strength, difficulty in industrial production, and difficulty in precipitation, etc., to reduce the amount of PVA powder, reduce white "pollution, and eliminate water pollution Effect

Pending Publication Date: 2022-05-03
CHINA PETROLEUM & CHEM CORP +2
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] When using traditional technology to produce low-viscosity polyvinyl alcohol products, especially ultra-low-viscosity polyvinyl alcohol, because the viscosity is very low, the product strength is not high, and when the degree of alcoholysis is high (degree of alcoholysis ≥ 80%), although it can be molded, it cannot be formed. The molding is extremely poor, almost completely pulverized, and industrial production is extremely difficult; if the degree of alcoholysis is low (≤80%), the product has a high solubility in methanol and is difficult to precipitate. The product is usually in the form of methanol solution or methanol / water mixed solution Existence, resulting in transportation difficulties (methanol solution is a hazardous chemical), inconvenient use, which seriously restricts the development, application and promotion of ultra-low viscosity PVA products

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0048] The production of PVA088-03 products, the specific steps are:

[0049] A. Preheating and polymerization: 50% vinyl acetate methanol solution with a mass concentration is preheated to 55°C by a preheater, and then enters the first polymerization kettle, at 0.1%wt (in terms of mass percentage of vinyl acetate) Bis(3,5,5-trimethylhexanoyl) peroxide

[0050] Solution polymerization under the action of initiator;

[0051] When the polymerization rate reaches 35.0%, the polymerization solution is sent to the second polymerization tank to continue polymerization, so that the polymerization rate rises to about 90%, and the polymerization reaction of vinyl acetate is carried out in methanol solution;

[0052] Set up a counter-current condenser on the polymerization kettle to condense the evaporated vinyl acetate and methanol vapors and return to the polymerization kettle, and use jacketed warm water to keep the polymerization temperature stable at 65°C. The total polymerization...

Embodiment 2

[0071] The production of PVA088-02 products, the specific steps are:

[0072] A. Preheating and polymerization: Preheat the methanol solution of vinyl acetate with a mass concentration of 46% to 55° C. through a preheater, enter the first polymerization kettle, and pass through 0.011% wt (in terms of the mass percentage of vinyl acetate) Solution polymerization under the action of oxidized bis(3,5,5-trimethylhexanoyl) initiator;

[0073] When the polymerization rate reaches 35.0%, the polymerization solution is sent to the second polymerization tank to continue polymerization, so that the polymerization rate rises to about 90%, and the polymerization reaction of vinyl acetate is carried out in methanol solution;

[0074] Set up a counter-current condenser on the polymerization kettle to condense the evaporated vinyl acetate and methanol vapors and return to the polymerization kettle, and use jacketed warm water to keep the polymerization temperature stable at 65°C. The total p...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
viscosityaaaaaaaaaa
thicknessaaaaaaaaaa
viscosityaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of polyvinyl alcohol, and particularly relates to a forming method of an ultralow-viscosity polyvinyl alcohol solid, vinyl acetate is used as a raw material, an alcohol substance is used as a solvent, the ultralow-viscosity polyvinyl alcohol solid is prepared through the steps of polymerization and alcoholysis, the viscosity of polyvinyl alcohol is smaller than or equal to 5 mPa.s, and a film forming procedure is further included after the alcoholysis procedure. The problem that ultra-low-viscosity polyvinyl alcohol cannot be molded into a solid is solved.

Description

technical field [0001] The invention belongs to the technical field of polyvinyl alcohol, and in particular relates to a method for forming an ultra-low viscosity polyvinyl alcohol solid. Background technique [0002] Polyvinyl alcohol (PVA) is a high-molecular polymer with a large number of strong hydrophilic hydroxyl groups. It is a white or light yellow powder or granular substance that is produced by alcoholysis of polyvinyl acetate in the presence of an alkaline catalyst. And made. Polyvinyl alcohol has good water solubility, adhesion and film-forming properties, and has good chemical stability, and is not damaged by fungi and molds ("Research on the performance of polyvinyl alcohol photosensitive adhesive", Jiang Zeying, Optical Technology , No. 5, 1984, the 1st-4th line of the 1st paragraph of the left column and the 1-4th line of the 2nd paragraph of the right column on page 3, published on December 31, 1984). [0003] At present, polyvinyl alcohol is widely used i...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08J3/12C08L29/04
CPCC08J3/12C08J2329/04
Inventor 侯双燕郭永松李永江戴祖贵郭海奇
Owner CHINA PETROLEUM & CHEM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap