Windbond MR 201P
WINDBOND MR 201P (E1 GRADE) Melamine urea formaldehyde resin is condensation copolymerization resin product and belongs to thermosetting group. It confirm to MR grade plywood with higher moist weather resistance. It is suitable in the manufacture of particle board, chip board panel. It is easily soluble in low/high atmospheric temperature and its relatively higher cost of raw material pay compensation with better quality of panel properties.
Melamine content in WINDBOND MR 201P (E1 GRADE) resin varies between 8.0 to 10.0 %
1. PHYSICAL PROPERTIES AND SPECIFICATIONS OF WINDBOND MR 201P (E1 GRADE)
|APPEARANCE||:||WHITE FREE FLOWING POWDER|
|VISCOSITY (1:1) AT 25°C||:||23 – 40 SEC IN B4 CUP|
|pH OF 50% SOLUTION AT 25°C||:||8.5 TO 10.0|
|GEL TIME||:||4.0 to 6.0 MINUTES|
|POT LIFE AT 30°C||:||6-7 HOURS|
|WATER TOLERANCE IN 50% SOLUTION (1:1)||:||1:1.0 to 1.3|
|SOLUBILITY||:||EASILY SOLUBLE IN WATER|
|FREE FORMALDEHYDE AT 50%SOLN.||:||<0.35%|
2. GLUE PREPARATION
|POWDER||:||100 PARTS BY WEIGHT|
|WATER||:||100-110PARTS BY WEIGHT|
|WHEAT FLOUR||:||8 TO 12 % OF TOTAL WEIGHT (POWDER + WATER)|
|HARDENER||:||0.05 TO 0.5% OF TOTAL WEIGHT DEPENDING ON WEATHER CONDITION|
|LIQUOR AMMONIA||:||TO MAINTAIN pH OF GLUE MIXTURE. pH SHOULD BE BETWEEN 6.5 TO 7.0|
3. GLUE MAKING PROCEDURE
The method of mixing will depend on the availability of equipment. Usual mixing method as given below
Take 50% of the total water in glue mixer. Add resin powder and required quantity of wheat our. Mix well for 15 20 minutes until all powder dissolved and lump free paste is prepared Then add rest of water and mix well for 10 minutes. Temperature may be maintained 20-35°C.
Check viscosity, if needed some water may be added to maintain the required viscosity 14-16 seconds in B6 cup.
Mix the hardener immediately before use.
4. REACTIVITY OF GLUE
Local conditions determine the selection of reactivity. The reactivity of the glue can be adjusted over a wide range by varying the composition and quantity of hardener. Hardener percentage is dependent on the wood chips pH, weather and plant parameters.
5. POT LIFE PROCESS
Pot life is the amount of time that the resin remains workable i.e. useable after addition of ammonium chloride. Take and mix properly powder 2 parts + water 1 part by weight. Then take 50 gm solution and add 2 gm solid ammonium chloride and stir continuously until the paste becomes rubbery. Note down the time, the pot life of particular paste.
6. GLUE CONSUMPTION
The veneer surface should be properly cleaned and free from dust and other contamination. Veneer should be at with uniform thickness. Veneers moisture content should be in between 8 to 10%. Between two adjoining veneers moisture content should not vary more than 2%.
In general, the consumption of glue varies between 300 to 450 gm per square meter based on manufacturing condition, veneer quality.
7. PRE-PRESSING AND HOT PRESSING CONDITION
Pre-pressing is suggested to ensure uniform glue transfer. Pre-pressing panel can be handled to increase productivity as well as prevent uneven glue spraying during loading in the hot press. The specific pressure should be 2-3 kg/sq.cm,pressing time varies from 15-30 minutes.
Hot pressing time and pressure varies for different wood density. Normally wood density varies from than 500 to 600 kg/cubic meter
For wood density less than 550 kg/cubic meter, Hot Press pressure 8-2 Kg/sq.cm and for wood density more than 550 kg/ cubic meter, Hot Press pressure 14-16 Kg/sq.cm
Hot press temperature to be maintained between 115 to 125°C depending on the thickness of veneer and Hot Press pressure.
Hot pressing time = Basic setting time (2 minutes) (equivalent to gel time) + Heat transfer time to the farthest glue line (normally 1 minute per mm; for 6 mm thickness, farthest glue line is 3 mm, so heat transfer time to the farthest glue line is 3 minute.)
After pressing, temperature of the boards should be brought down to a minimum level before stacking, otherwise there may be deterioration of the board.
The equipment like glue mixer, spreader should be cleaned with warm water and this should be done before the glue is completely cured. The addition of slight urea to the water will facilitate cleaning process.
9. MAJOR APPLICATION AREAS
For the making of moisture resistance grade plywood, MDF, laminated veneer lumber, Particle Board.
WINDBOND MR 201P has application where boards with low formaldehyde emissions are required.
25 Kg packing available in HDP/PP bag with polyethylene liner.
During handling powder, it is wise to use hand gloves to avoid direct skin contact. Hands and other contact area should be washed with soap and hot water before meal and when handling is over. Dust Mask can be used.
Store in original bags in a cool and dry place to protect from heat and moisture absorption. Resin is hygroscopic and will pick up moisture from atmospheric air. Bags not be kept open and should be properly closed during storage. Storage life at 25°C: 12 months.