Ammonio Methacrylate Copolymer Dispersion
»Ammonio Methacrylate Copolymer Dispersion is an aqueous dispersion of Ammonio Methacrylate Copolymer Type Aor Bin water.It may contain suitable antimicrobial preservatives and alkalizing agents.The assay requirements differ for the two types,as set forth in the accompanying table.
Ammonio methacrylate units,dried basis (%)
Type Min Max
A 10.18 13.73
B 6.11 8.26
Packaging and storage— Preserve in tight containers,at a temperature not exceeding 25for Type A,and not exceeding 30for Type B.Protect from freezing.
Labeling— Label it to state whether it is Type Aor Type B.Label it to indicate the name and quantity of any added antimicrobial preservative or alkalizing agent.
USP Reference standards á11ñ— USP Ammonio Methacrylate Copolymer Type A RS.USP Ammonio Methacrylate Copolymer Type B RS.
Identification—
A:Infrared Absorption á197Kñ— Proceed as directed,except to use the residue obtained in the test for Loss on dryingas the test specimen.
B: It meets the requirements of the test forViscosity and the Assay.
Viscosity á911ñ— Use a viscosimeter equipped with a spindle having a cylinder 1.88cm in diameter and 6.51cm high attached to a shaft 0.32cm in diameter.The distance from the top of the cylinder to the lower tip of the shaft is 0.75cm,and the immersion depth is 8.15cm.Adjust the temperature to 20±0.10.With the spindle rotating at 30rpm,immediately record the scale reading.Multiply the scale reading by the constant for the viscosimeter spindle and speed employed,to obtain the viscosity in centipoises.The viscosity is not more than 100centipoises.
Loss on drying á731ñ— Dry it at 110for 6hours:it loses between 68.5%and 71.5%of its weight.
Residue on ignition á281ñ— Using mild heating conditions (e.g.,steam bath,sand bath,etc.)to avoid loss of material,evaporate the dispersion to dryness prior to ignition:not more than 0.5%of residue is obtained,calculated on the undried dispersion basis.
Limit of monomers— Proceed as directed in the test for Limit of monomers under Ammonio Methacrylate Copolymer:not more than 0.002%of methyl methacrylate and not more than 0.008%of ethyl acrylate are found.
Coagulum content— Accurately weigh a stainless steel sieve having 125-µm openings,and filter 100g of Dispersion through it.Wash the sieve with distilled water until a clear filtrate is obtained,and dry the sieve to constant weight at 105:the weight of the residue does not exceed 1000mg (1%).
Assay— Dry under vacuum 2g of Ammonio Methacrylate Copolymer Dispersion Type A,or 4g of Ammonio Methacrylate Copolymer Dispersion Type B,at 90for 30minutes.Dissolve in 75mLof glacial acetic acid at about 50,within about 30minutes.After the solution has cooled down,add 25mLof 0.6%cupric acetate solution in glacial acetic acid,and titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically.Perform a blank titration,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 20.772mg of ammonio methacrylate (C9H18ClNO2)units.
Auxiliary Information— Staff Liaison:Catherine Sheehan,B.Sc.,Scientist
Expert Committee:(EMC)Excipients:Monograph Content
USP28–NF23Page 2956
Pharmacopeial Forum:Volume No.29(6)Page 2011
Phone Number:1-301-816-8262