A kind of heat preservation rigid melamine foam with low water absorption rate and preparation method thereof

A technology with low water absorption rate and water absorption rate, applied in the field of polymer materials, can solve the problems of inability to effectively hinder the penetration of water, low closed cell rate of melamine foam, and increased thermal conductivity, so as to reduce the water absorption rate and thermal conductivity of foam, and improve the The proportion of hydrophobic groups, the effect of improving thermal insulation performance

Active Publication Date: 2022-06-21
HEFEI UNIV OF TECH
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

And the closed cell rate of melamine foam is low, and the open cell foam structure cannot effectively prevent water from penetrating into the cells.
If the insulation material is permeated by water for a long time, its thermal conductivity will increase, the mechanical properties of the foam will deteriorate and the service life will be shortened

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
  • A kind of heat preservation rigid melamine foam with low water absorption rate and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] The preparation operation steps of a kind of low water absorption rate thermal insulation rigid melamine foam are as follows:

[0023] (1) 176.7g of distilled water, 112.7g of paraformaldehyde, and 150g of melamine were successively added to the three-necked flask, and mixed and stirred at 85°C for 10 minutes to obtain a clear solution;

[0024] (2) 18g n-butanol and 1.2g hexamethylenetetramine were added to the clear solution, and the reaction was continued for 2.40h. After the reaction was completed, it was rapidly cooled to 30°C using a cold water bath to obtain a modified melamine resin prepolymerization solution;

[0025] (3) When the viscosity of the melamine resin prepolymer solution to be modified reaches 30Pa·s, add 2g nano-silica (100nm), 4g dimethyl silicone oil, 10g n-pentane to 200g modified melamine resin prepolymer solution alkane and 1.5g dodecylbenzenesulfonic acid, stir at a high speed of 1300r / min for 2min, then add 1.4g hydrochloric acid and stir at ...

Embodiment 2

[0028] The preparation operation steps of a kind of low water absorption rate thermal insulation rigid melamine foam are as follows:

[0029] (1) 176.7g of distilled water, 112.7g of paraformaldehyde, and 150g of melamine were successively added to the three-necked flask, and mixed and stirred at 85°C for 10 minutes to obtain a clear solution;

[0030] (2) 9g of n-butanol and 1.1g of hexamethylenetetramine were added to the clear solution, and the reaction was continued for 2.30h. After the reaction was completed, it was rapidly cooled to 30°C using a cold water bath to obtain a modified melamine resin prepolymerization solution;

[0031] (3) When the viscosity of the melamine resin prepolymer solution to be modified reaches 40Pa·s, add 4g nano-silica (100nm), 4.2g dimethyl silicone oil, 11g positive Pentane and 1g of dodecylbenzenesulfonic acid were stirred at a high speed of 1300r / min for 2.5min, and then 1.3g of hydrochloric acid was added and stirred at a high speed for 35...

Embodiment 3

[0034] The preparation operation steps of a low water absorption rate thermal insulation rigid melamine foam are as follows;

[0035] (1) 176.7g of distilled water, 112.7g of paraformaldehyde, and 150g of melamine were sequentially added to the three-necked flask, and mixed and stirred at 80°C for 10 minutes to obtain a clear solution;

[0036] (2) Add 18g n-butanol and 1.3g hexamethylenetetramine to the clear solution, and continue the reaction for 2.50h. After the reaction, use a cold water bath to rapidly cool to 25°C to obtain a modified melamine resin prepolymer solution ;

[0037] (3) When the viscosity of the melamine resin prepolymer solution to be modified reaches 35Pa s, add 2g micron silica (5um), 4g dimethyl silicone oil, 10g n-pentane and 1.4g tenon to 200g resin prepolymer solution. Dialkylbenzenesulfonic acid, stirred at a high speed of 1300 r / min for 2 minutes, then added 1.4 g of oxalic acid and stirred at a high speed for 25 s; foamed in an oven for 40 minut...

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
limiting oxygen indexaaaaaaaaaa
water absorptionaaaaaaaaaa
limiting oxygen indexaaaaaaaaaa
Login to view more

Abstract

The invention relates to a heat-preserving rigid melamine foam with a low water absorption rate and a preparation method thereof, belonging to the technical field of polymer materials. The density of the low water absorption thermal insulation rigid melamine foam is less than 53kg / m 3 , The water absorption rate is as low as 6.7%, the thermal conductivity is as low as 0.034W / m·K, the closed cell rate is 80%, the compressive strength is 300kPa, and the limiting oxygen index is as high as 35%. In the preparation process of the present invention, small molecules of short-chain hydrophobic alcohols and solid fillers are added; side groups of the molecular chains of the melamine resin prepolymer modified by small molecules of short-chain hydrophobic alcohols are introduced into "hanging" short-chain hydrophobic alkyl groups, Effectively improve the hydrophobicity of the resin, and at the same time, the increase of the "hanging" short chain content with better flexibility can improve the toughness of the resin and reduce the foam pulverization rate; in the preparation stage of the modified hydrophobic melamine prepolymer foaming liquid, solid fillers are added as The nucleating agent can adjust the cell structure, and can effectively reduce the free energy barrier of the growth of the cell nuclei to promote the heterogeneous nucleation, and prepare the low water absorption thermal insulation rigid melamine foam with small cell size and uniform distribution.

Description

technical field [0001] The invention belongs to the technical field of polymer materials, and relates to a preparation method of a low water absorption rate thermal insulation rigid melamine foam. Background technique [0002] Rigid melamine foam, also known as rigid melamine formaldehyde foam, is a foam material prepared from melamine resin through a certain foaming process. Due to its special triazine ring structure, a dense carbon layer can be rapidly formed on the surface of the foam to isolate oxygen and generate a large amount of N during the combustion process. 2 , so that the foam has intrinsic flame retardancy and is widely used in building fire protection materials. Since there are still unreacted hydrophilic groups (-NH-, -OH) in the melamine foam matrix, it is easy to form hydrogen bonds with water molecules in the air, increasing the hydrophilicity of the foam matrix. In addition, the closed cell ratio of melamine foam is low, and the open-cell foam structure ...

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 Patents(China)
IPC IPC(8): C08L61/32C08K7/26C08K9/06C08J9/14C08G12/42
CPCC08J9/141C08J9/0071C08J9/009C08G12/427C08J2361/32C08K2201/011C08K7/26C08K9/06C08J2203/14
Inventor 马海红杨心愿李春晖任凤梅周正发徐卫兵
Owner HEFEI UNIV OF TECH
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