1、Designation: D817 12Standard Test Methods of TestingCellulose Acetate Propionate and Cellulose AcetateButyrate1This standard is issued under the fixed designation D817; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 butyrates. Theseesters m
3、ay 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 test procedures appear i
4、n 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 Sulfate Content 51-5
5、6Viscosity 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 applicability of regulatorylimi
6、tations prior to use.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD1343 Test Method for Viscosity of Cellulose Derivativesby Ball-Drop MethodD2929 Test Method for Sulfur Content of Cellulosic Mate-rials by X-Ray FluorescenceD5897 Test Method for Deter
7、mination of Percent Hydroxylon Cellulose Esters by Potentiometric TitrationAlternative Method3. Reagents3.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analyt
8、ical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.4. Conditioning4.1 ConditioningConditi
9、on 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 D618, for those tests where conditioning is required.In cases of disagreement, the tolerances shall be 61C(61.8F) and 62 % relative humidity.4.2
10、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(61.8F) and 62 % relative humidity.MOISTURE CONTENT5. Procedure5.1 Transfe
11、r 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 the jurisdiction of ASTM Committee D01 onPaint and Related Coatings, Mat
12、erials, and Applications and are the directresponsibility of Subcommittee D01.36 on Cellulose and Cellulose Derivatives.Current edition approved Nov. 1, 2012. Published January 2013. Originallyapproved in 1944. Last previous edition approved in 2010 as D817 96 (2010).DOI: 10.1520/D0817-12.2For refer
13、enced 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.3Reagent Chemicals, American Chemical Society Specifications, AmericanC
14、hemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), R
15、ockville,MD.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16. Calculation6.1 Calculate the percentage of moisture as follows:Moisture, % 5 A/B! 3100 (1)where:A = weight loss on heating, g, andB = sample used, g.ASH7. Significance and
16、 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 stabilityand optical clarity of a cellulose ester in melt processing or actas a potential source of insolubles when the ester
17、 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 over a flame in a 100-mLtared platinum crucible that has been heated to constant weightand weighed to the nearest 0
18、.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 long as the residue burns with aflame. Transfer the crucible to a muffle furnace and heat at 550to 600C for 3 h, or
19、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 roomtemperature, weigh accurately to the nearest 0.1 mg.9. Calculation9.1 Calculate the percentage of ash as follows:Ash, % 5 A/B! 3100 (2)whe
20、re: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 Use11.1 Free acidity is a measure of unesterified organic acid inthe ester. The presence of high levels of free acid is
21、 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 0.1g of methyl red in 3.72 mL of 0.1000 N NaOH solution anddilute to 250 mL with water. Filter if necessary.12.3 Phenolph
22、thalein 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 0.01 N solution of sodium hydroxide(NaOH).Test Method AFor Samples Containing Not More thanAbout 30 % Propionyl or Butyryl
23、13. 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 it tostand for 3 h. Filter off the cellulose ester and wash it withwater. Titrate the combined filtrate and washings wi
24、th 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. Calculation14.1 Calculate the percentage of acidity as free acetic acidas follows:Free acetic acid, % 5 $A 2 B!C 30.06#/W% 3100
25、(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 Samples Containing More than About7 % Propionyl or Butyryl and Particularly Suitable forSamples Containing More than 30
26、 % 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 dissolved, add 50 mL of water andshake well to precipitate the ester in a finely divided form.Add3 drops of methyl red
27、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 content as acetic acid asdirected in Section 14.17. Precision and Bias17.1 No statement on bias can be made as no referencema
28、terial is available as a standard.APPARENT ACETYL CONTENT18. Scope18.1 The test methods described in the following Sections20 to 26 cover the determination of the saponification value ofD817 122the sample calculated as percentage of apparent acetyl, equiva-lent weight 43. This value is required in t
29、he calculation ofacetyl and propionyl or butyryl contents in 36.1.18.2 The test method used should be specified or agreedupon. The choice depends on the propionyl or butyryl contentand the physical condition of the sample. Ordinarily, TestMethod A is recommended for samples having less than about35
30、% 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 ester. Apparent acetyl value is required inthe calculation of acetyl, propionyl, and butyryl content in36.1.Test Meth
31、od 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 or aluminum, approximately 137 mmsquare, containing 25 compartments 25 mm square. Eachcompartment shall have the correc
32、t 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 (convenient but not essential).20.3 Buret, automatic zero, 35-mL, 25-mL bulb, stemgraduated from 25 to 35 mL in 0.05-mL
33、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 NH2SO4.20.5 Buret, 5-mL, in 0.01 or 0.1-mL divisions, for backtitration with 0.1 N NaOH solution.20.6 Magnetic Stirrer, for
34、 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 critical.21. Reagents21.1 AcetoneAdd one 30-mL portion of 1.0 N NaOHsolution to a mixture of 150 mL acetone and 100 mL hot w
35、ater,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, andtitrate as above. The difference between the two titrations shallnot exceed 0.05 mL.21.2 Dimethyl Sulfoxide.21.3 P
36、yridine.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 standardize a 0.1 N solution of NaOH.21.6 Sulfuric Acid Standard (1.0 N)Prepare and standard-ize a 1.0 N solution of sulfuric
37、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 weighing bottlefor2hat1056 3C and weigh 1.9 6 0.05 g of the driedsample by difference to the nearest 1 mg into a 500-mLE
38、rlenmeyer 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 entireprocedure.NOTE 1Potassium acid phthalate is used so that the concentration ofthe NaOH in contact with the solvent
39、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, thusavoiding errors caused by using a different buret for the titration of theblank and the sample or by refilling the 15
40、-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 10 mL ofwater and swirl to mix. Stopper the flask and allow it to standwith occasional swirling until solution is compl
41、ete. 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 stopper. It isessential that complete solution be effected.22.3 For acetone-insoluble samples of low propionyl orbutyryl c
42、ontent, 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 flask.Add 70 mL of acetone to the flask and swirl gently until thesample particles are completely wetted and evenly dispe
43、rsed.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 flask towash down any sample particles clinging to the side. Stopperthe flask and allow it to stand with occasional swi
44、rling 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 acetoneand swirl or stir for 5 min. Proceed in accordance with 22.4.22.3.2 Dimethyl sulfoxide is the preferred solvent,
45、 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 the mixtureto stand undisturbed for 20 min. Add 75 mL of pyridinewithout shaking or swirling and allow the mixture to
46、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 homogeneous andall large gel masses are broken down into individual highlyswollen particles. When these highly swollen gel
47、particles arewell dispersed and are not fused together in large gel masses,D817 123no further heating is necessary. Cool the flask, add 30 mL ofacetone, and swirl or stir for 5 min.22.4 Add 30 mL of NaOH solution (40 g/L) with constantswirling or stirring to the solution of the sample and also to th
48、eblank. 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 flaskand let the mixture stand with occasional swirling or stir on themagnetic stirring unit. Allow 30 min for sap
49、onification 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 stirring until theend point is reached; then add an excess of 0.2 or 0.3 mL ofH2SO4. Allow the mixture to stand with occasional sti
