1、Designation: D4690 12 (Reapproved 2018)Standard Specification forUrea-Formaldehyde Resin Adhesives1This standard is issued under the fixed designation D4690; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specification covers three types of urea
3、-formaldehyde thermosetting resin adhesives suitable for use onwood, wood-based substrates, or plastic laminates.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation only.1.3 The requirements for the adhesive are based on te
4、sts ofphysical properties including viscosity, density, nonvolatilecontent, pH, insoluble matter, amylaceous matter, mixingproperties, working life, and on strength properties, includingdry shear strength in lumber-type joints, dry and wet shearstrength in plywood-type joints, and all strength tests
5、 at the endof the storage life certified by the manufacturer.1.4 The following safety hazards caveat pertains only to thetest method portion, Sections 8 through 11, of this specifica-tion: This standard does not purport to address all of the safetyconcerns, if any, associated with its use. It is the
6、 responsibilityof the user of this standard to establish appropriate safety,health, and environmental practices and determine the appli-cability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-
7、ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2B417 Test Method for Apparent Density of Non-Free-
8、Flowing Metal Powders Using the Carney FunnelD905 Test Method for Strength Properties of AdhesiveBonds in Shear by Compression LoadingD906 Test Method for Strength Properties of Adhesives inPlywood Type Construction in Shear by Tension LoadingD907 Terminology of AdhesivesD1084 Test Methods for Visco
9、sity of AdhesivesD1489 Test Method for Nonvolatile Content of AqueousAdhesivesD1490 Test Method for Nonvolatile Content of Urea-Formaldehyde Resin SolutionsD1583 Test Method for Hydrogen Ion Concentration of DryAdhesive FilmsD1875 Test Method for Density of Adhesives in Fluid FormD2556 Test Method f
10、or Apparent Viscosity of AdhesivesHaving Shear-Rate-Dependent Flow Properties Using Ro-tational ViscometryD5266 Practice for Estimating the Percentage of WoodFailure in Adhesive Bonded JointsE70 Test Method for pH of Aqueous Solutions With theGlass ElectrodeE104 Practice for Maintaining Constant Rel
11、ative Humidityby Means of Aqueous Solutions2.2 Federal Specifications:3PPP-C-96 Cans, Metal, 28 Gage and LighterPPP-D-723 Drums, FiberPPP-D-729 Drums, Shipping and Storage, Steel, 55-gal(208-L)2.3 Federal Standard:3FED-STD-123 Marking for Shipment2.4 Military Standard:3MIL-STD-129 Marking for Shipme
12、nt and Storage3. Terminology3.1 DefinitionsMany terms in this specification are de-fined in Terminology D907.3.2 Definitions of Terms Specific to This Standard:1This specification is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.30 on W
13、oodAdhesives.Current edition approved Aug. 1, 2018. Published August 2018. Originallyapproved in 1987. Last previous edition approved in 2012 as D4690 12. DOI:10.1520/D4690-12R18.This specification is intended as a replacement for Federal SpecificationMMM-A-188c, Adhesive; Urea Resin Type (Liquid an
14、d Powder).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 Standardization Documents Order Des
15、k, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recogni
16、zed principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.2.1 lotadhesive manufactured at one place from thesame batch or
17、blends of raw materials subjected to the sameoperations and conditions.NOTE 1In this specification, the maple block lamination in TestMethod D905 and the birch plywood construction in Test Method D906are described as assemblies.4. Significance and Use4.1 This specification provides testing procedure
18、s and speci-fies requirements to differentiate between the physical andadhesive bonding properties of the many commercial urea-formaldehyde thermosetting resin and catalyst systems.4.2 Because of the diverse nature of products bonded withthese adhesives, testing by this specification will only evalu
19、atethe adhesive under a given set of conditions. The physicalproperties of the adhesive are measured to provide informationon certain handling and working properties. The adhesive-bonding properties are measured on maple block and birchplywood specimens, prepared and tested in accordance withTest Me
20、thod D905 and Test Method D906, respectively. Thecertification requirements have been based on knowledgewithin the industry of values that may be expected. TestMethod D905 and Test Method D906 have a long history ofuse in many specifications.4.3 The stress calculated by using this specification shou
21、ldnot be used to predict failure nor should it be used for designstress in joints with different geometry or loading directiondifferent from the test geometry.5. Classification5.1 Urea resin adhesive shall be furnished as one of thefollowing types:5.1.1 Type APowder with separate curing agent.5.1.2
22、Type BPowder with incorporated curing agent.5.1.3 Type CLiquid with separate curing agent.NOTE 2Type A, Type B, and Type C replace the Type I, Type II, andType III classifications of Federal Specification MMM-A-188C,respectively, to prevent confusion with Type I (boil test) and Type II(cold-water so
23、ak) classifications used in existing ASTM standards foradhesives.6. Test Requirements6.1 To meet the requirements of this specification, the urearesin and adhesive mix shall be subjected to the tests listed inSection 10. In addition, the adhesive shall meet the require-ments of the tests described i
24、n Section 11 and as listed in Table1.6.2 To meet the storage-life requirements, an initial lot ofthe adhesive shall be tested in accordance with Sections 10 and11. It shall pass all test requirements after being stored underconditions and time specified by the manufacturer. Followingthis initial tes
25、t, certification shall be based on submission fromthe manufacturer.6.3 The curing agent for Types A and C shall readilydisperse in the adhesive mixture when used in accordance withthe manufacturers recommendation.6.4 The filler shall neither dissolve nor swell excessively inwater, and shall not sett
26、le from the adhesive mixture during theworking life.7. Retest and Rejection7.1 When a specimen fails at a load less than that specified,if the wood failure is 50 % or greater, that specimen shall bedisregarded in computing the average. If more than one third ofthe test specimens for any one test con
27、dition are discarded forthis reason, the test shall be repeated.7.2 If the results of any initial test do not conform to therequirements prescribed in this specification, that test shall berepeated on an additional set of specimens made from the samelot of adhesive, each set of which shall conform t
28、o therequirements specified. If this set of specimens fails to meet therequirements, the lot shall be rejected.TEST METHODS8. Significance and Use8.1 This specification provides testing procedures to differ-entiate between the physical and adhesive bonding propertiesof the many commercial urea-forma
29、ldehyde thermosettingresin and catalyst systems.9. Sampling9.1 Take a representative, 2-L (2-qt) sample of adhesivefrom the lot to be tested. Divide the sample into two equalportions and place each in a wide mouth, glass, 1-L (1-qt)container and seal tightly. Use one of the samples for tests ofphysi
30、cal and adhesive bond properties (Sections 10 and 11),and use the other for testing storage life (11.2.3.3), and for anyretesting that may be necessary under Section 7. Also, takesufficient quantity of curing agent to cure the adhesive samplesand place in a separate, clean, dry container. Seal all s
31、amplecontainers with well-fitting, corrosion-resistant lids.10. Physical Properties10.1 Test the physical properties of adhesives by the fol-lowing test methods:10.1.1 Viscosity:10.1.1.1 Measure the viscosity of the liquid urea resin oradhesive mixtures in accordance with Test Methods D1084 orD2556.
32、TABLE 1 Test RequirementsTest Section NumberTest Requirement(Minimum)Block shear (compression)Dry at 24C (75F) 11.1 19 306 kPa (2800 psi)Plywood shear (tension)Dry at 24C (75F) 11.2.3.1 2 344 kPa (340 psi)48-h soak 11.2.3.2 1 930 kPa (280 psi)Storage life 11.2.3.3AAA retained sample of the initial l
33、ot of the adhesive shall be tested and shall meetthe requirements of all tests listed in 6.2 for the applicable type of adhesive afterthe storage life time certified by the manufacturer.D4690 12 (2018)210.1.1.2 Temperature of TestCondition to, and maintainthe liquid urea resin or adhesive mixture at
34、 24 6 0.5C (75 61F) during the viscosity reading. Other temperatures may beused upon agreement between the contracting parties, but the60.5C (61F) tolerance must be observed.10.1.1.3 For Type C adhesives requiring the addition of acuring agent, make two viscosity measurements of the testadhesives (1
35、) before the addition of curing agent, and (2) afterthe addition of the curing agent. The viscosity of urea resinsfollowing addition of curing agent to liquid resin is time-dependent. Make the measurement 10 min after mixing.10.1.2 Density:10.1.2.1 Measure the density of dry-powder adhesives orsepar
36、ate curing agents in accordance with Test Method B417,and report in grams per cubic centimetre (pounds per cubicfoot). (See Appendix X1.)10.1.2.2 Measure the density of Type C adhesives in accor-dance with Test Method D1875 and report in grams permillilitre (pounds per gallon).10.1.3 Nonvolatiles:10
37、.1.3.1 Determine the nonvolatile content of Type A andType B from a 100-g mixture of adhesive and water (preparedby manufacturers instructions) and test in accordance withTest Method D1490.10.1.3.2 Determine the nonvolatile content of the uncata-lyzed Type C liquid adhesive in accordance with Test M
38、ethodD1490.10.1.4 pH of Cured Adhesive FilmDetermine the pH ofthe cured adhesive film in accordance with Test MethodD1583.10.1.5 Insoluble MatterDetermine the quantity of in-soluble matter in Type B adhesives, including filler and anyinsoluble material, as a percentage of the nonvolatile constitu-en
39、ts of the adhesive when determined as specified in 10.1.3.1.Weigh to the nearest milligram approximately2goffreshlymixed adhesive in a 100-mL beaker and add 50 mL of coldsolution of 20 parts by volume of glacial acetic acid and 80parts by volume of distilled water. Stir the mixture thoroughlyfor 1 m
40、in and then add 0.500 6 0.001 g, acid-washeddiatomaceous earth (see Note 6). Stir the mixture for 2 minmore and then filter through a fritted-glass crucible of mediumporosity with the aid of a vacuum. Transfer all residue to thefilter with a 20 % acetic acid solution. Wash the residue on thefilter w
41、ith at least 50 mL of 20 % acetic acid and then with colddistilled water to remove the acid. Dry the crucible in an ovenat 124 6 3C (255 6 5C) for 1 to 112 h, cool in a desiccator,and weigh to the nearest milligram. The insoluble content, as apercentage of the nonvolatile content, is determined as f
42、ollows:Percent insoluble 5 Weight of residue 2 0.500! (1)3100/Weight of adhesive 3percent nonvolatile!NOTE 3“Filter-61” and “Celite Analytical Filter-Aid” have beenfound satisfactory. Diatomaceous earth is prepared by acid-wash, ovendried at 124 6 3F (155 6 5C) and then cooled in a desiccator.10.1.6
43、 Amylaceous Matter in Type B AdhesiveAdd a dropof solution made from5gofiodine,5gofpotassium iodide,and 100 mL of distilled water, to approximately 0.5 g ofadhesive mix on a porcelain spot plate or watch glass. Adarkening of the mixture denotes the presence of amylaceousmatter.10.1.7 Mixing Properti
44、es and Working Life, Mix approxi-mately 200 g of adhesive (in accordance with the manufactur-ers instruction) in a 400-mL beaker (Note 6) with a stirring rodor blade. Allow the beaker to stand without a cover in air at 246 2.5C (75 6 5F). If necessary, place in a water bath toobtain the proper tempe
45、rature. Stir the adhesive frequently andnote the time at which the adhesive is considered no longerspreadable. At the end of the working life, note whether theadhesive is in a homogeneous condition. In case of doubt as towhether the adhesive is spreadable, test the adhesive at 24 62.5C (75 6 5F) usi
46、ng a Brookfield Viscometer. Consider theadhesive to be at the end of its working life when it reaches aviscosity of 600 P (0.6 Pas). If the temperature of the bondingoperation is 32.2C (90F) or higher, the above test may beconducted at 32.2C (90F).NOTE 4A disposable beaker or a 473-mL (16-oz) plasti
47、c cup may beused.11. Adhesive-Bonding Properties11.1 Block-Shear Strength (Compression) Tests:11.1.1 Prepare and test specimens in accordance with TestMethod D905. Use the adhesive manufacturers instructionsfor conditions and procedures for preparing and spreading theadhesive, and assembling, pressi
48、ng, and curing of the assem-bly. Use a two-week curing period unless otherwise instructedby the adhesive manufacturer.11.1.2 Number of SpecimensTest 20 specimens represent-ing at least four assemblies.11.1.3 Dry Shear TestCondition one test group of 20specimens to 10 to 12 % moisture content at 24 6
49、 1C (75 62F) and test in accordance with Test Method D905. Apply theload with a continuous motion of the movable loading head ata rate of 12.7 mm (0.5 in.)/min (610 %).NOTE 5To obtain the desired moisture content refer to Table 3-4 onpage 3-8 of the Wood Handbook.4Additional information is available inPractice E104. Constant temperature and relative humidity cabinets areavailable from laboratory supply companies.11.1.4 CalculationCalculate the shear stress at failure inkilopascals per square inch by dividing the specimens break-ing lo
