1、Designation: D 817 96 (Reapproved 2004)Standard Test Methods of TestingCellulose Acetate Propionate and Cellulose AcetateButyrate1This standard is issued under the fixed designation D 817; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover procedures for the testing ofcellulose acetate propionates and acetate but
3、yrates. Theseesters may vary widely in composition and properties, socertain of the procedures can be used only in the ranges ofcomposition where they are suitable.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 The tes
4、t procedures appear in the following sections:SectionsAcetyl Propionyl or Butyryl Contents 28-37Acetyl Content, Apparent 18-27Acidity, Free 12-17Ash 7-10Color and Haze 77-81Heat Stability 57-65Hydroxyl Content 38-44Hydroxyl Content, Primary 46-50Intrinsic Viscosity 67-71Moisture Content 5-6Sulfur or
5、 Sulfate Content 51-56Viscosity 74-75Limiting Viscosity Number 67-711.4 This standard does not purport to address the safetyconcerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicabil
6、ity of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 618 Practice for Conditioning Plastics for TestingD 1343 Test Method for Viscosity of Cellulose Derivativesby Ball-Drop MethodD 2929 Test Method for Sulfur Content of Cellulosic Ma-terials by X-Ray FluorescenceD 5
7、897 Test Method for Determination of Percent Hydroxylon Cellulose Esters by Potentiometric TitrationAlternativeMethod2.2 ASTM Adjuncts:Color and Haze Apparatus33. Reagents3.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reage
8、nts shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening thea
9、ccuracy of the determination.4. Conditioning4.1 ConditioningCondition the test specimens at 23 62C (73.4 6 3.6F) and 50 6 5 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A ofPractice D 618, for those tests where conditioning is required.In cases of disagreement
10、, the tolerances shall be 6 1C(61.8F) and 62 % relative humidity.4.2 Test ConditionsConduct tests in the Standard Labora-tory Atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specified in the test meth-ods. In cases of disagreements, the tolerances shall be 61C(61.8
11、F) and 6 2 % relative humidity.MOISTURE CONTENT5. Procedure5.1 Transfer about5gofthesample to a tared, low,wide-form weighing bottle and weigh to the nearest 0.001 g.Dry in an oven for2hat1056 3C. Remove the bottle fromthe oven, cover, cool in a desiccator, and weigh.1These test methods are under th
12、e jurisdiction of ASTM Committee D01 onPaint and Related Coatings, Materials, and Applications and are the directresponsibility of Subcommittee D01.36 on Cellulose and Cellulose Derivatives.Current edition approved June 1, 2004. Published June 2004. Originallyapproved in 1944. Last previous edition
13、approved in 1996 as D 817 96.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from ASTM Internation
14、al Headquarters. Order Adjunct No.ADJD0817.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dor
15、set, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Calculation6.1 Calculate the percentage of moisture as f
16、ollows:Moisture, % 5 A/B! 3 100 (1)where:A = weight loss on heating, g, andB = sample used, g.ASH7. Significance and Use7.1 Ash content gives an estimate of the inorganic contentof cellulose ester samples. The presence of high levels ofinorganic content (ash) can be detrimental to the melt stability
17、and optical clarity of a cellulose ester in melt processing or actas a potential source of insolubles when the ester is used insolution.8. Procedure8.1 Dry the sample for2hat1056 3C and weigh 10 to 50g, to the nearest 0.01 to 0.1 g, depending on its ash content andthe accuracy desired. Burn directly
18、 over a flame in a 100-mLtared platinum crucible that has been heated to constant weightand weighed to the nearest 0.1 mg. Add the sample in portionsif more than 10 g is taken. The sample should burn gently andthe portions should be added as the flame subsides. Continueheating with a burner only as
19、long as the residue burns with aflame. Transfer the crucible to a muffle furnace and heat at 550to 600C for 3 h, or longer if required, to burn all the carbon.Allow the crucible to cool and then transfer it, while still warm,to a desiccator. When the crucible has cooled to room tem-perature, weigh a
20、ccurately to the nearest 0.1 mg.9. Calculation9.1 Calculate the percentage of ash as follows:Ash, % 5 A/B! 3 100 (2)where:A = ash, g, andB = sample used, g.10. Precision and Bias10.1 No statement on bias can be made as no referencematerial is available as a standard.FREE ACIDITY11. Significance and
21、Use11.1 Free acidity is a measure of unesterified organic acid inthe ester. The presence of high levels of free acid is potentiallydetrimental to melt processing of the ester and can impact theodor of the ester.12. Reagents12.1 Acetone, neutral.12.2 Methyl Red Indicator Solution (0.4 g/L)Dissolve 0.
22、1g of methyl red in 3.72 mL of 0.1000 N NaOH solution anddilute to 250 mL with water. Filter if necessary.12.3 Phenolphthalein Indicator Solution (1 g/100 mL)Dissolve 1 g phenolphthalein in 100 mL of ethyl alco-hol (95 %).12.4 Sodium Hydroxide, Standard Solution (0.01 N)Prepare and standardize a 0.0
23、1 N solution of sodium hydroxide(NaOH).Test Method AFor Samples Containing Not More thanAbout 30 % Propionyl or Butyryl13. Procedure13.1 Shake5gofthesample, corrected for moisture contentif necessary, in a 250-mL Erlenmeyer flask with 150 mL offreshly boiled, cold water. Stopper the flask and allow
24、it tostand for 3 h. Filter off the cellulose ester and wash it withwater. Titrate the combined filtrate and washings with 0.01 NNaOH solution, using phenolphthalein indicator solution.13.2 Run a blank determination on the water, using the samevolume as was used in extracting the sample.14. Calculati
25、on14.1 Calculate the percentage of acidity as free acetic acidas follows:Free acetic acid, % 5 $A 2 B!C 3 0.06/W% 3 100 (3)where:A = NaOH solution used to titrate the sample, mL,B = NaOH solution used to titrate the blank, mL,C = normality of the NaOH solution, andW = sample used, g.Test Method BFor
26、 Samples Containing More than About7 % Propionyl or Butyryl and Particularly Suitable forSamples Containing More than 30 % Propionyl or Butyryl15. Procedure15.1 Dissolve 10.0 g of the sample, corrected for moisturecontent if necessary, in 200 mL of neutral acetone plus 20 mLof water. When completely
27、 dissolved, add 50 mL of water andshake well to precipitate the ester in a finely divided form. Add3 drops of methyl red indicator solution and titrate to alemon-yellow end point and 0.01 N NaOH solution.15.2 Make a blank determination on the reagents.16. Calculation16.1 Calculate the free acid cont
28、ent as acetic acid asdirected in Section 14.17. Precision and Bias17.1 No statement on bias can be made as no referencematerial is available as a standard.APPARENT ACETYL CONTENT18. Scope18.1 The test methods described in the following 20 to 26cover the determination of the saponification value of t
29、hesample calculated as percentage of apparent acetyl, equivalentweight 43. This value is required in the calculation of acetyland propionyl or butyryl contents in 36.1.D 817 96 (2004)218.2 The test method used should be specified or agreedupon. The choice depends on the propionyl or butyryl contenta
30、nd the physical condition of the sample. Ordinarily, TestMethod A is recommended for samples having less than about35 % propionyl or butyryl and Test Method B for sampleshaving more than that amount.19. Significance and Use19.1 Apparent acetyl content is a measure of the saponifi-cation value of the
31、 ester. Apparent acetyl value is required inthe calculation of acetyl, propionyl, and butyryl content in36.1.Test Method AFor Samples Containing Less than About35 % Propionyl or Butyryl20. Apparatus20.1 Weighing Bottle, glass-stoppered, 15-mL capacity,25-mm diameter by 50 mm high.20.2 Tray, copper o
32、r aluminum, approximately 137 mmsquare, containing 25 compartments 25 mm square. Eachcompartment shall have the correct dimensions to contain oneweighing bottle. The entire tray shall fit inside a desiccator andshould have a basket-type handle to facilitate the introductionand removal of the tray (c
33、onvenient but not essential).20.3 Buret, automatic zero, 35-mL, 25-mL bulb, stemgraduated from 25 to 35 mL in 0.05-mL increments; or pipet,automatic zero, 30-mL for NaOH solution (40 g/L).20.4 Buret, automatic zero, 15-mL, 10-mL bulb, stemgraduated from 10 to 15 mL in 0.05-mL increments, for 1 NH2SO
34、4.20.5 Buret, 5-mL, in 0.01 or 0.1-mL divisions, for backtitration with 0.1 N NaOH solution.20.6 Magnetic Stirrer, for single flask.20.7 Magnetic Stirrer, capacity twelve or more flasks.20.8 Stirring Bars, stainless steel Type 416, length 50 mm,diameter 5 to 6 mm or equivalent, dimensions not critic
35、al.21. Reagents21.1 AcetoneAdd one 30-mL portion of 1.0 N NaOHsolution to a mixture of 150 mL acetone and 100 mL hot water,allow to stand with frequent swirling for 30 min, and titratewith 1.0 N H2SO4. Add another 30-mL portion of 1.0 N NaOHsolution to 100 mL of hot water, allow to stand for 30 min,
36、 andtitrate as above. The difference between the two titrations shallnot exceed 0.05 mL.21.2 Dimethyl Sulfoxide.21.3 Pyridine.21.4 Sodium Hydroxide Solution (40 g/L)Dissolve 40 g ofsodium hydroxide (NaOH) in water and dilute to 1 L.21.5 Sodium Hydroxide, Standard Solution (0.1 N)Prepare and standard
37、ize a 0.1 N solution of NaOH.21.6 Sulfuric Acid Standard (1.0 N)Prepare and stan-dardize a 1.0 N solution of sulfuric acid (H2SO4).21.7 Phenolphthalein Indicator Solution (1 g/100 mL)Dissolve1gofphenolphthalein in 100 mL of ethyl alcohol(95 %).22. Procedure22.1 Dry the ground well-mixed sample in we
38、ighing bottlefor2hat1056 3C and weigh 1.9 6 0.05 g of the driedsample by difference to the nearest 1 mg into a 500-mLErlenmeyer flask. Prepare a blank by drying approximately 3.8g of potassium acid phthalate and weighing it by difference intoa flask as described above. Carry the blank through the en
39、tireprocedure.NOTE 1Potassium acid phthalate is used so that the concentration ofthe NaOH in contact with the solvent in the blank will be approximatelythe same as that in contact with the sample and so that the titration of theblank will be approximately the same as the titration of the sample, thu
40、savoiding errors caused by using a different buret for the titration of theblank and the sample or by refilling the 15-mL buret. If desired, however,the potassium acid phthalate may be omitted.22.2 For acetone-soluble sample, put the sample into solu-tion as follows: Add 150 mL of acetone and 5 to 1
41、0 mL ofwater and swirl to mix. Stopper the flask and allow it to standwith occasional swirling until solution is complete. Solutionmay be hastened by magnetic stirring or by any suitablemechanical shaking that will provide a gentle rocking type ofagitation to avoid splashing the solution on the stop
42、per. It isessential that complete solution be effected.22.3 For acetone-insoluble samples of low propionyl orbutyryl content, dissolve the sample by either of the followingtwo methods:22.3.1 Gently rotate the flask by hand to distribute andspread the sample in a thin layer over the bottom of the fla
43、sk.Add 70 mL of acetone to the flask and swirl gently until thesample particles are completely wetted and evenly dispersed.Stopper the flask and allow it to stand undisturbed for 10 min.Carefully add 30 mL of dimethyl sulfoxide from a graduate tothe flask, pouring the solvent down the sides of the f
44、lask towash down any sample particles clinging to the side. Stopperthe flask and allow it to stand with occasional swirling untilsolution is complete. Magnetic stirring or gentle mechanicalagitation that will not splash the solution is recommended.When solution appears to be complete, add 50 mL of a
45、cetoneand swirl or stir for 5 min. Proceed in accordance with 22.4.22.3.2 Dimethyl sulfoxide is the preferred solvent, but if itis not available, spread the sample in a thin layer over thebottom of the flask, add 15 mL of acetone, swirl to wet theparticles with acetone, stopper the flask, and allow
46、the mixtureto stand undisturbed for 20 min. Add 75 mL of pyridinewithout shaking or swirling and allow the mixture to stand for10 min. Heat the solution just to boiling and swirl or stir for 5min. Again heat to boiling and swirl or stir for 10 min.Continue to heat and stir until the mixture is homog
47、eneous andall large gel masses are broken down into individual highlyswollen particles. When these highly swollen gel particles arewell dispersed and are not fused together in large gel masses,no further heating is necessary. Cool the flask, add 30 mL ofacetone, and swirl or stir for 5 min.22.4 Add
48、30 mL of NaOH solution (40 g/L) with constantswirling or stirring to the solution of the sample and also to theblank. Use of a magnetic stirrer is recommended (Note 2). It isabsolutely necessary that a finely divided precipitate of regen-erated cellulose, free of lumps, be obtained. Stopper the flas
49、kD 817 96 (2004)3and let the mixture stand with occasional swirling or stir on themagnetic stirring unit. Allow 30 min for saponification oflower acetyl samples, 2 h for high acetyl samples whendimethyl sulfoxide is the solvent, and 3 h when pyridine is thesolvent. At the end of the saponification period, add 100 mL ofhot water, washing down the sides of the flask, and stir for 1 or2 min. Add 4 or 5 drops of phenolphthalein indicator solutionand titrate the excess NaOH solution with 1.0 N H2SO4(Note3). Titrate rapidly with constant swirling or stirr
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