EPA Method 312C Determination Of Residual Styrene In Sbr Latex Produced By Emulsion Polymerization
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ID： |
FA4FDAC3608A4C9AA858C9F52427B5D0 |
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文件大小(MB)： |
0.02 |
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页数： |
8 |
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文件格式： |
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日期： |
1998-5-13 |
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文本摘录（文本识别可能有误，但文件阅览显示及打印正常，pdf文件可进行文字搜索定位）：
1,METHOD 312C - DETERMINATION OF RESIDUAL STYRENE,IN SBR LATEX PRODUCED BY EMULSION POLYMERIZATION,1.0 SCOPE,1.1 This method is applicable for determining the amount of,residual styrene in SBR latex as produced in the emulsion,polymerization process.,2.0 PRINCIPLE OF METHOD,2.1 A weighed sample of latex is coagulated in 2-propanol,which contains alpha-methyl styrene as an Internal Standard.,The extract from the coagulation will contain the alphamethyl,styrene as the Internal Standard and the residual,styrene from the latex. The extract is analyzed by a Gas,Chromatograph. Percent styrene is calculated by relating,the area of the styrene peak to the area of the Internal,Standard peak of known concentration.,3.0 DEFINITIONS,3.1 The definitions are included in the text as needed.,4.0 INTERFERENCES,(Reserved),5.0 SAFETY,5.1 When using solvents, avoid contact with skin and eyes.,Wear hand and eye protection. Wash thoroughly after,use.,5.2 Avoid overexposure to solvent vapors. Handle only in,well ventilated areas.,6.0 EQUIPMENT AND SUPPLIES,6.1 Gas Chromatograph - Hewlett Packard 5890, Series II,with flame ionization detector, or equivalent.,Column - HP 19095F-123, 30m x 0.53mm, or equivalent.,Substrate HP FFAP (cross-linked) film thickness 1,micrometer. Glass injector port liners with silanized,glass wool plug.,Integrator - HP 3396, Series II, or equivalent.,2,6.2 Wrist action shaker,6.3 Automatic dispenser,6.4 Automatic pipet, calibrated to deliver 5.0 +0.01 grams,of latex,6.5 Four-ounce wide-mouth bottles with foil lined lids,6.6 Crimp cap vials, 2ml, teflon lined septa,6.7 Disposable pipets,6.8 Qualitative filter paper,6.9 Cap crimper,6.10 Analytical balance,6.11 10ml pipette,6.12 Two-inch funnel,7.0 REAGENTS AND STANDARDS,7.1 2-Propanol (HP2C grade),7.2 Alpha methyl styrene (99+% purity),7.3 Styrene (99+% purity),7.4 Zero air,7.5 Hydrogen (chromatographic grade),7.6 Helium,7.7 Internal Standard preparation,7.7.1 Weigh 5.000-5.005 grams of alpha-methyl styrene into a,100ml volumetric flask and bring to mark with 2-,propanol to make Stock "A" Solution.,Note: Shelf life - 6 months,7.7.2 Pipette 10ml of Stock "A" Solution into a 100ml,volumetric flask and bring to mark with 2-propanol to,Wx,’FxxWis(Ax/Ais),3,prepare Stock "B" Solution.,7.7.3 Pipette 10ml of the Stock "B" solution to a 1000ml,volumetric flask and bring to the mark with 2-,propanol. This will be the Internal Standard Solution,(0.00005 grams/ml).,7.8 Certification of Internal Standard - Each batch of,Stock "B" Solution will be certified to confirm,concentration.,7.8.1 Prepare a Standard Styrene Control Solution in 2-,propanol by the following method:,7.8.1.1 Weigh 5.000 +.005g of styrene to a 100ml,volumetric flask and fill to mark with 2-propanol,to make Styrene Stock "A" Solution.,7.8.1.2 Pipette 10ml of Styrene Stock "A" Solution to a,100ml volumetric flask and fill to mark with 2-,propanol to make Styrene Stock "B" Solution.,7.8.1.3 Pipette 10ml of Styrene Stock "B" soluion to a,250ml volumtric flask and fill to mark wtih 2-,propanol to make the Certification Solution.,7.8.2 Certify Alpha-Methyl Styrene Stock "B" Solution.,7.8.2.1 Pipette 5ml of the Certification Solution and 25ml,of the Alpha Methyl Styrene Internal Standard,Solution to a 4-oz. bottle, cap and shake well.,7.8.2.2 Analyze the resulting mixture by GC using the,residual styrene method. (11.4-11.6 of this,method),7.8.2.3 Calculate the weight of alpha methyl styrene,present in the 25ml aliquat of the new Alpha,Methyl Styrene Standard by the following equation:,where Ax = Peak area of alpha methyl styrene,4,Ais = Peak area of styrene,Wx = Weight of alpha methyl styrene,Wis = Weight of styrene (.00100),Fx = Analyzed response factor = 1,The Alpha Methyl Styrene Stock Solution used to,prepare the Internal Standard Solution may be considered,certified if the weight of alpha methyl styrene analyzed by,this method is within the range of .00121g to .00129g.,8.0 SAMPLING,8.1 Collect a latex sample in a capped container. Cap the,bottle and identify the sample as to location and,time.,8.2 Deliver sample to Laboratory for testing within one,hour.,8.3 Laboratory will test within two hours.,8.4 No special storage conditions are required.,9.0 QUALITY CONTROL,9.1 The laboratory is required to operate a formal quality,control program. This consists of an initial,demonstration of the capability of the method as well,as ongoing analysis of standards, blanks, and spiked,samples to demonstrate continued performance.,9.1.1 When the method is first set up, a calibration is run,and the recovery efficiency for each type of sample,must be determined.,9.1.2 If new types of sa……
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