VMCH Resin is made from high molecular weight and made of carboxyl-functional terpolymer comprised of vinyl chloride, vinyl acetate, and Maleic Acid
They have a composition of %
Vinyl chloride by mass 86 %
Vinyl acetate content by mass 13%
Maleic acid by mass 1%
Molecular weight 27000
Specific gravity 1.35
2. VMCH Coating Full Name
VMCH is vinyl chloride, vinyl acetate and maleic acid
3. Why VMCH Coating On Aluminium Foil?
Aluminium foil is used to pack pharmaceutical finished products in Alu-Alu and blister packing, cold-form packaging. Aluminium foil sealing with PVC or cold-form foil aluminium foil requires an adhesive. The adhesives are LDPE, Heat seal lacquer, and VMCH. When the heat is provided, the adhesive is sealed to aluminium foil to rigid PVC, cold form, or other rigid layer.
The VMCH is as a powder. VMCH provides good adhesion to vinyl, metals, concrete, and cellulosic substrates. The VMCH gives highly flexible post-formable coating on aluminium foil. This terpolymer contains a carboxyl group, which has good aluminium foil adhesion. It has good resistance to alkali, base brine salty mist, and oil Easter and alcohols.
Then we called the VMCH coating used on the foil as the adhesive form to aluminium foil to rigid PVC
4. GSM Testing of VMCH Coated Aluminium foil.
- Selected sample of VMCH-Coated Aluminium foil 10 x 10 cm or 5 X 5 cm is suitable with the help of GSM Plate. Weight the sample at analytical balance. and record it
- Total Grammage = weight in gram x 100 or 400( if the sample is cut 10 x 10 cm or 5 x 5 cm)
- Dip cotton or clean cloth in ethyl acetate and rub on the VMCH-Coating layer side until the VMCH is removed. After some time, the sample was dried at room temperature. Then take weight on analytical balance. And record it
Grammage of aluminium layer = weight in gram x 100 or 400 (if the sample cut 10 x 10 cm or 5 x 5 cm)
Grammage of HSL Layer = total Grammage- Grammage of the aluminium layer
OR
- Regent 10% NaoH
- Take 10 gm of sodium hydroxide in a 100 ml volumetric flask. Add 50 ml water mix and sonication the sample then make up with water. It made 10% sodium hydroxide
- Take a sample of total Grammage, Make a solution of 10% NaoH. Dip the sample in its solution after some time, and the aluminium layer dissolved. The remaining layers are found in the VMCH Layer. Dry it at room temperature and after taking the weight sample
Grammage VMCH layer = weight in gram x 100 or 400 (if the sample cut 10 x 10 cm or 5 x 5 cm)
5. Identification testing of VMCH-coated foil.
The identification test of the drug in the contact layer is VMCH. It test was performed with an FTIR instrument. It’s standard to use a ZEON. ITS plots spectra wavelength 3800-650 cm-1
It gives FTIR GRAPH of VMCH
I am Maneesh Maurya a professional pharmaceutical blogger from India having rich experience in the pharmaceutical Quality control field.
[…] cotton or clean cloth in ethyl acetate and rub on the VMCH-Coating layer until the VMCH is removed. After some time, the sample was dried at room temperature. Then take […]
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