Preparation method of alkoxy-terminated polydimethylsiloxane

A technology of hydroxyl polydimethylsiloxane and dimethylsiloxane is applied in the field of preparation of alkoxy-terminated polydimethylsiloxane, which can solve the problems affecting production efficiency, viscosity peak and poor storage stability. and other problems, to achieve the effect of high end capping efficiency, less addition and high stability

Active Publication Date: 2021-10-19
新纳奇材料科技江苏有限公司
View PDF2 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Because organotin is used as the catalyst, it is easy to form a monoalkoxy polymer with no crosslinking activity, which has the problem of poor storage stability; if titanate is used as the catalyst, it will form due to the interaction between titanate and the terminal hydroxyl group of 107 silicone rubber. Viscosity peaks will appear in the false cross-linked state, seriously affecting production efficiency

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of alkoxy-terminated polydimethylsiloxane

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Prepare the alkoxy terminated polydimethylsiloxane as follows:

[0026] (1) Mix DMC and hexamethyldisiloxane and heat up to 170°C, add phosphoric acid dropwise, stir at 300r / min for 7 hours, reflux to remove water to obtain silicon phosphate terminator, DMC, hexamethyldisiloxane The mass ratio of oxane to phosphoric acid is 70:10:15.

[0027] (2) Warm up the linear body to 150°C, add potassium hydroxide aqueous solution with a mass concentration of 10%, and then stir the polycondensation reaction, monitor the viscosity online, and add the silicon phosphate terminator obtained in step (1) before reaching the target viscosity of 1000mPa·s, After continuing the reaction for 50 minutes, the low-boiling point substances were removed by vacuum vacuum distillation to obtain hydroxyl silicone oil. The mass ratio of linear body, potassium hydroxide aqueous solution, and silicon phosphate terminator was 40000:1:1.5.

[0028] (3) Add a certain proportion of methyltrimethoxysilane...

Embodiment 2

[0031] Prepare the alkoxy terminated polydimethylsiloxane as follows:

[0032] (1) Mix DMC and hexamethyldisiloxane and heat up to 170°C, add phosphoric acid dropwise, stir at 300r / min for 7 hours, reflux to remove water to obtain silicon phosphate terminator, DMC, hexamethyldisiloxane The mass ratio of oxane to phosphoric acid is 70:10:15.

[0033] (2) Warm up the linear body to 150°C, add potassium hydroxide aqueous solution with a mass concentration of 10%, and then stir the polycondensation reaction, monitor the viscosity online, and add the silicon phosphate terminator obtained in step (1) before reaching the target viscosity of 20000mPa·s, After continuing the reaction for 50 minutes, the low-boiling point substances were removed by vacuum vacuum distillation to obtain hydroxyl silicone oil. The mass ratio of linear body, potassium hydroxide aqueous solution, and silicon phosphate terminator was 40000:1:1.5.

[0034] (3) Add a certain proportion of methyltrimethoxysilan...

Embodiment 3

[0037] Prepare the alkoxy terminated polydimethylsiloxane as follows:

[0038] (1) Mix DMC and hexamethyldisiloxane and heat up to 170°C, add phosphoric acid dropwise, stir at 300r / min for 7 hours, reflux to remove water to obtain silicon phosphate terminator, DMC, hexamethyldisiloxane The mass ratio of oxane to phosphoric acid is 70:10:15.

[0039] (2) Warm up the linear body to 150°C, add potassium hydroxide aqueous solution with a mass concentration of 10%, and then stir the polycondensation reaction, monitor the viscosity online, and add the silicon phosphate terminator obtained in step (1) before reaching the target viscosity of 20000mPa·s, After continuing the reaction for 50 minutes, the low-boiling point substances were removed by vacuum vacuum distillation to obtain hydroxyl silicone oil. The mass ratio of linear body, potassium hydroxide aqueous solution, and silicon phosphate terminator was 40000:1:1.5.

[0040] (3) Add a certain proportion of methyltrimethoxysilan...

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
Login to view more

Abstract

The invention discloses a preparation method of alkoxy-terminated polydimethylsiloxane, wherein the preparation method comprises the following steps: (1) mixing DMC and hexamethyldisiloxane, heating to 160-180 DEG C, dropwise adding phosphoric acid, stirring for 6-8 hours, and refluxing to remove water to obtain a silicon phosphate terminator; and (2) heating a linear body to 130-150 DEG C, adding a potassium hydroxide aqueous solution, stirring for condensation polymerization, monitoring the viscosity on line, adding the silicon phosphate terminator obtained in the step (1) before the target viscosity is reached, continuously reacting for 5-50 minutes, vacuumizing, carrying out reduced pressure distillation to remove low-boiling-point substances, and thus obtaining the alpha,omega-dihydroxy polydimethylsiloxane with different viscosities. By adopting the preparation method of the alkoxy-terminated polydimethylsiloxane with the structure, the prepared alkoxy-terminated polydimethylsiloxane has the advantages of high terminating efficiency, convenient production process and good storage stability.

Description

technical field [0001] The invention relates to the technical field of organosilicon polymerization, in particular to a preparation method of alkoxy-terminated polydimethylsiloxane. Background technique [0002] Traditional dealcoholized silicone rubber is generally made of 107 silicone rubber as the base rubber, combined with fillers, crosslinking agents, catalysts, coupling agents, plasticizers, etc. Because organotin is used as the catalyst, it is easy to form a monoalkoxy polymer with no crosslinking activity, which has the problem of poor storage stability; if titanate is used as the catalyst, it will form due to the interaction between titanate and the terminal hydroxyl group of 107 silicone rubber. Viscosity peaks will appear in the false cross-linked state, seriously affecting production efficiency. [0003] Alkoxy-terminated polydimethylsiloxane, even if titanate-based catalysts are used in the production of alcohol-based adhesives, there will be no viscosity peaks...

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): C08G77/20C08G77/18C08G77/08
CPCC08G77/20C08G77/18C08G77/08
Inventor 余跃徐守彬
Owner 新纳奇材料科技江苏有限公司
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