Low formaldehyde melamine adhesive with expanding characteristic and preparation method

A technology of melamine and low free formaldehyde, applied in the field of preparation of water-based low free formaldehyde melamine resin, can solve the problems of increasing the cost of resin, affecting the mechanical properties and service performance of adhesives and their products, and achieving the effect of excellent storage performance

Inactive Publication Date: 2005-07-20
倪卓
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The introduction of these additives will increase the cost of the resin and affect the mechanical properties and performance of the adhesive and its 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

[0012] Add appropriate proportions of formaldehyde, melamine and water into the reactor, and the molar ratio of formaldehyde / melamine is 1.5-2.5. Adjust pH with Lewis base or acid, in the range of 8-12. After the mixture is reacted at 50°C-80°C for 1-2 hours, 1%-10% of organic substances are added. Continue the reaction at 50°C to 100°C for 2-4 hours. When the viscosity reached 30-60 cps, the mixture was cooled slowly. If necessary, the pH value can be adjusted to between 8.5 and 10 to obtain melamine resin.

[0013] The obtained melamine resin has the following typical properties:

[0014] Solid content 50%

[0015] Viscosity 30-60cps

[0016] PH value 9.2-9.7

[0017] Specific gravity 1.22g / ml

[0018] Free formaldehyde 0.1%

[0019] Storage period 14 days

Embodiment 2

[0021] The melamine resin in Example 1 is sent into the feeding tank of the spray dryer, and the liquid glue is sent into the high-speed centrifugal atomizer by the speed-regulating feed pump, and the misty glue enters the drying main tower and is heated by the hot air from the heating furnace. When heated (180°C), the moisture in the glue liquid evaporates quickly, and part of the powdered glue falls into the lower part of the drying tower (100°C), and the residence time is about 10 seconds. The prepared powder melamine formaldehyde adhesive has the following characteristics:

[0022] Appearance white powder

[0023] Particle size <80 mesh

[0024] Moisture content 3%

[0025] Apparent density 0.6-0.8

[0026] Formaldehyde content 0.3%

[0027] Storage period 1 year

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

No PUM Login to view more

Abstract

The melamine resin prepared with formaldehyde and melamine as main material and in the presence of Lewis acid or alkali has free formaldehyde content of about 0.1 %. The adhesive possesses excellent expansion performance during formation and is suitable for use in producing various kinds of board. The products with the adhesive have low formaldehyde release amount, excellent mechanism performance, excellent weather resistance, etc. The liquid resin may be spray dried to prepare melamine adhesive powder capable of maintaining reaction activity for long time. The adhesive of the present invention has no need of adding formaldehyde trapping agent.

Description

1. Technical field [0001] The present invention discloses a process for the preparation of waterborne low free formaldehyde melamine resins based on melamine and formaldehyde, which can be used to form industrial articles with limited formaldehyde release; due to the pronounced swelling properties of the adhesive when cured, it is especially suitable for Manufacture of various panel products such as particle board, fibreboard and plywood. The powder melamine resin prepared by the dry spraying process maintains the characteristics of the liquid melamine resin and also has excellent storage properties. 2. Technical background [0002] Melamine resin adhesives are widely used in many fields of industry and life. Melamine resin has the advantages of low cost, good reactivity, and convenient processing. In the production process, the curing speed of the resin can be adjusted by adding a catalyst (resin hardener), so the production capacity is greatly increased and the working cy...

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): C08G14/10
Inventor 倪卓
Owner 倪卓
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