Designation:D4802–02An American National Standard Standard Specification for
Poly(Methyl Methacrylate)Acrylic Plastic Sheet1
This standard is issued under thefixed designation D4802;the number immediately following the designation indicates the year of
original adoption or,in the ca of revision,the year of last revision.A number in parenthes indicates the year of last reapproval.A
superscript epsilon(e)indicates an editorial change since the last revision or reapproval.
1.Scope*
1.1This specification covers monolithic methacrylate sheets produced by various process.For this specification,meth-acrylate sheet shall be compod of polymerized acrylic monomers of which at least80%shall be methyl methacrylate. N OTE1—This specification is intended to consolidate the requirements of the Cast Methacrylate Plastic Sheets portion of discontinued Fed.Spec. L-P-391D,discontinued Specification D70
2.Cast Methacrylate Plastic Sheets,Rods,Tubes and Shapes,and discontinued Specification D1547, Extruded Acrylic Plastic Sheet.
1.2This specification is intended to cover acrylic sheet for general-purpo applications.For specialty applications con-sult the appropriate u standards.
1.3The following safety hazards caveat pertains only to the test methods portion,Section8,of this specification:This standard does not purport to address all of the safety concerns, if any,associated with its u.It is the responsibility of the ur of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limita-tions prior to u.
1.4Acrylic sheet is ud frequently in applications in which extreme clarity,lack of optical distortion and abnce of any foreign particulate matter are of primary significance.Re-ground material may be
ud as long as careful control is ud to eliminate adver effects on the properties.The u of recycled material in type B-1and B-2sheet,may have adver effects on the properties which would preclude its u in most cas.The u of recycled or reground material is not possible for type A-1and A-2materials since the sheet is produced directly from monomer
N OTE2—This standard is similar to ISO7823-1:1987(E)in title only. The technical content is significantly different.
2.Referenced Documents
2.1ASTM Standards:
D256Test Methods for Determining the Izod Pendulum Impact Resistance of Plastics2
D542Test Methods for Index of Refraction of Transparent Organic Plastic2
D570Test Method for Water Absorption of Plastics2
D638Test Method for Tensile Properties of Plastics2
D648Test Method for Deflection Temperature of Plastics Under Flexural Load in the Edgewi Position2
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D792Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by Displacement2
D883Terminology Relating to Plastics2
D1003Test Method for Haze and Luminous Transmittance of Transparent Plastics2
D1044Test Method for Resistance of Transparent Plastics to Surface Abrasion2
D1308Test Method for Effect of Houhold Chemicals on Clear and Pigmented Organic Finishes3
D2565Practice for Xenon Arc Exposure of Plastics In-tended for Outdoor Applications4
D3002Guide for Evaluation of Coatings Applied to Plas-tics3
D3359Test Method for Measuring Adhesion by Tape Test5 D3892Practice for Packaging/Packing of Plastics4
E29Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications6
2.2ISO Standard:奖学金英文
ISO7823-1:1987(E)Plastics—Poly(Methyl Methacrylate) Sheets—Types,Dimensions,and Characteristics7
3.Terminology
3.1Definitions:
3.1.1General—The definitions given in Terminology D883are applicable to this specification.
3.2Definitions of Terms Specific to This Standard:
3.2.1bow warp,n—distortion in the form of a simple curve or arc extending across the sheet and displaced from the horizontal when the sheet is layingflat.
3.2.2edge kink warpage,n—distortion in the form of a twist,wrinkle,or scallop occurring along the perimeter of the sheet.
1This specification is under the jurisdiction of ASTM Committee D20on Plastics and is the direct responsibility of Subcommittee D20.15on Thermoplastic Materials.
Current edition approved March10,2002.Published May2002.Originally published as D4802–88.Last previous edition D4802–01.
2Annual Book of ASTM Standards,V ol08.01.
3Annual Book of ASTM Standards,V ol06.02.
4Annual Book of ASTM Standards,V ol08.02.
5Annual Book of ASTM Standards,V ol06.01.
6Annual Book of ASTM Standards,V ol14.02.
7Available from American National Standards Institute,25W.43rd St.,4th Floor,New York,NY10036.
1
*A Summary of Changes ction appears at the end of this standard.
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3.2.3“S”warp,n—distortion in the form of a compound curve or“S”shape caud by a nonuniform change in internal stress.
4.Classification
4.1Categories:
4.1.1Category A-1—Methacrylate sheet typically manufac-tured by the cell-casting process.This category reprents the best optical-quality sheet.It is characterized by the highest long-term design stress and the highest degree of chemical resistance found in methacrylate sheet.
4.1.2Category A-2—Methacrylate sheet typically manufac-tured by the continuous-casting method.The physical,chemi-cal,and thermal properties are similar to Category A-1sheet. The optical quality is lower than Category A-1sheet.This category has better thickness control than that of Category A-1 sheet.
4.1.3Category B-1—Methacrylate sheet manufactured by any of veral process(typically described as continuously manufactured sheet).This sheet posss lower heat,chemi-cal,and stress-craze resistance than Category A-1and Cat-egory A-2sheet.It has equivalent or better optical quality and thickness tolerances than Category A-2sheet.
4.1.4Category B-2—Methacrylate sheet typically manufac-tured by conventional extrusion process.This sheet is char-acterized by excellent thickness control similar to Category A-2and Category B-1sheet.This sheet has reduced long-term design stress,chemical resistance,optical quality,and thermal stability.
4.2Finish—The followingfinishes of methacrylate sheet may be specified.The physical and optical properties in this specification are bad on Finish1material unless otherwi noted.
4.2.1Finish1—Smooth or polished.
4.2.2Finish2—Patterned,including textures and frosting.
4.2.3Finish3—Abrasion-resistant coated.
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4.2.3.1Finish3material can be of any category provided it meets the requirements of that category plus the additional requirements listed in Table1.
4.2.4Type UVF(UV-Filtering)—Materials that contain an ultraviolet absorber to limit the transmission of UV radiation through the sheet especially for protection of items nsitive to sunlight or UV radiation.
4.2.5Type UVT(UV-Transmitting)—Materials that do not contain any UV absorbers and are ud where there is a need to transmit a greater portion of UV radiation.
4.2.6For general-purpo applications neither type need be specified.If not specified,materials will usually contain UV absorbers only sufficient to protect the polymer from degrada-tion from exposure to direct sunlight or UV radiation.There are no specific UV-transmission requirements for material of unspecified type.
5.Detail Requirements
5.1The following applies to all specified limits in this specification.For purpos of determining conformance with this specification,an obrved value or a calculated value shall be rounded to the nearest1MPa(100psi)for tensile strength, and for all other properties shall be rounded to the nearest unit in the last righthand place of digits ud in expressing the limiting value,in accordance with the rounding method of Practice E29.
5.2Sheet shall conform to the requirements prescribed in Table2.In addition,Category A-1sheet shall conform to the permissible-thickness variations listed in Table3.
5.3Shrinkage—Test in accordance with8.1.7.
5.4Thermal Stability—Sheet shall show no evidence of bubbling or blistering when tested in accordance with8.1.8.
5.5Abrasion-Resistant Material—Finish3material (abrasion-resistant coated material)shall meet the requirements of the substrate material it is designated as and the properties shown in Table1.
5.6Workmanship—Sheet,as delivered,shall be free from warpage,cracks,scratches,blisters,voids,foreign matter,die lines,and other defects that may affect appearance or rvice-ability.
5.6.1Flatness of Sheet—Sheet shall be free from edge kink warpage and from edge“S”warp when lying on aflat surface. Overall bow warp is permitted for all types of sheet to a maximum of 6.3mm(0.250in.)displacement from the horizontal for each4-ft length,or fraction thereof,of a sheet under its own weight when laying in the horizontal position on aflat continuous surface.“S”warp that disappears or becomes bow warp when turned over is permitted.
5.6.2Chips and Dirt in Sheet:
5.6.2.1Chips in Sheet of Thickness Equal to or Less Than 51mm(2.008in.)—The maximum permissible chip size shall be 3.2mm(0.125in.).Chips that are approximately the maximum permissible size shall not have a frequency greater than1chip per0.4m2(4.3ft2)of sheet area.Chips less than0.8 mm(0.031in.)are to be disregarded unless they form a concentrated pattern that may affect rviceability.Chips from 0.8mm(0.031in.)to the maximum permissible size shall not have a frequency greater than1per0.4m2(4.3ft2).Chips out of tolerance in size may be knifed off and considered accept-able if the remaining blemish can be removed by polishing, except for Finish3sheet which cannot be easily polished.For Finish3sheet,the maximum permissible chip size shall be 4.75mm(0.187in.);all other requirements above apply except as noted.
5.6.2.2Chips in Sheet of Thickness Greater Than51mm (2.008in.)—Chips may be accepted providing they do not extend more than0.4mm(0.016in.)above the surface.
5.6.2.3Dirt and Contaminants—The maximum permissible dirt and contamination dimension shall be3.2mm(0.125in.). Dirt and contaminants less than0.8mm(0.031in.)shall be disregarded unless they form a concentrated pattern that may
TABLE1Finish3Abrasion Resistant Material
Property Test Method Requirement Abrasion resistance,100cycles at
500g load
D1044
Haze,max,% 4.0
Coating adhesion,percent retention, min e8.1.14Minimum Classification
4B,Fig.1,Test
Methods D3359
Chemical resistance,visual examination D1308no
change
affect the rviceability of the sheet.The maximum permissible frequency for dimensions ranging from 0.8mm (0.031in.)to the maximum permissible for each type of sheet shall be 1per 0.4m 2(4.3ft 2)of sheet area for thickness up to and including 12.0mm (0.472in.).For Finish 3sheet the maximum permissible dimension for dirt and contaminants shall be 4.8mm (0.187in.);all other requirements above apply.
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5.6.2.4Other Defects —Minor defects,such as mold or handling scratches,or die lines that can be removed by polishing,shall be permitted provided the are not objection-able individually or in group patterns.Excluding side letgoes for masked and unmasked sheets in thickness greater than
51mm (2.004in.)and for unmasked sheets that are thicker than 6.0mm (0.236in.)up to and including 51mm (2.004in.),defects within 25mm (0.984in.)of the untrimmed edge of the sheet,that do not significantly reduce mechanical strength of the sheet,shall be permitted.Side letgoes for sheets thicker than 51mm (2.004in.)may exist providing they do not extend more than 0.4mm (0.016in.)below the surface.Side letgoes for unmasked sheets thicker than 6.0mm (0.236in.)up to and including 51mm (2.004in.)shall be allowed within a 50mm (1.97in.)band from the untrimmed edge of the sheet.For Finish 3sheet,the maximum permissible length for mold
scratches shall be 25mm (0.984in.);the maximum permissible length for medium or heavy handling scratches or abrasions shall be 50mm (1.97in.);the maximum permissible length of light-handling scratches or abrasions shall be 153mm (6.024in.);and scratches or abrasions less than 6mm shall be disregarded unless they form a concentrated pattern that may affect the rviceability of the sheet.For Finish 3sheet,the maximum permissible frequency for allowable scratches and abrasions as defined above shall be one per 0.4m 2(4.3ft 2)of sheet area.6.Sampling
6.1Unless otherwi indicated in Section 8or Table 2,lect a sample from a sheet 3.0mm thick sufficient to determine conformance of the material to this specification.
N OTE 3—When 6.0-mm-thickness sheet is not available for sampling for spectral-transmittance measurement,other thickness may be ud for sampling with adjustment of the values found to 6.0-mm thickness.Sheet thicker than 3.0mm may be lected when agreed upon between the purchar and the manufacturer.In that ca,it may be necessary to machine test specimens to 3.2-mm thickness,which is required for some tests.
TABLE 2Detail Requirements for Cast Methacrylate Plastic Sheets
Property
Test Method Category
A-1
A-2
B-1
B-2
Tensile strength,min,MPa (psi)D 63862(9.0k)62(9.0k)62(9.0k)62(9.0k)Elongation at break,min,%D 6382222A Index of refraction D 542
min: 1.48 1.48 1.48 1.48A max:
1.50
1.50 1.50 1.50Specific gravity D 792
min: 1.18 1.18 1.18 1.18A max:
1.20
1.20 1.20 1.20Luminous transmittance,min,%D 1003
<4.5mm (0.177in.)
91919191>4.5mm (0.177in.)#32mm (1.259in.)89898989>32.0mm (1.259in.)#51.0mm (2.000in.)87
878787Spectral transmittance,max,%e 8.1.12
Type UVF only 200to 400nm 5
5
5
5
(6.0mm,0.236in.)
Type UVT only 290to 400nm (3.0mm,0.118in.)@290nm 40404040@310nm 70707070@340nm 85858585@400nm 86868686Haze,max,%
D 1003
3
3
3
3
Dimensional tolerance,max:Thickness,%
e Table 3
610
65
65
Length and width,mm (in.)−0.0,+6.4(−0.0,+0.250)−0.0,+6.4(−0.0,+0.250)−0.0,+6.4(−0.0,+0.250)−0.0,+6.4(−0.0,+0.250)Shrinkage,max,%e 8.1.7
2.8 Transver:......0.0 5.0Machine:
...
...
3.08.0
Water absorption,%
D 570(24-h method)e Fig.1Fig.1
...
A
Deflection temperature under flexural load,1820
kPa (264psi),°C (°F),min D 648
<12.0mm (0.472in.)
87(188.6)87(188.6)87(188.6)87(188.6)>12.0mm (0.472in.)#24.0mm (0.944in.)88(190.4)88(190.4)88(190.4)N/A B >24.0mm (0.944in.)#100mm (3.937in.)93(199.4)93(199.4)N/A B
N/A B
Thermal stability
e 8.1.8.1e 8.1.8.1e 8.1.8.2e 8.1.8.2Impact strength,Izod,J/m (ft-lb/in.),min
D 256,Method A
16.0(0.3)
16.0(0.3)16.0(0.3)16.0(0.3)A
A For Category B-2sheet only,properties noted may be determined on the resin from which the sheet is extruded.B
Not
applicable.
TABLE3Permissible Thickness Variations for Category C-1Cast
Methacrylate Plastic Sheets
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Nominal Thickness,
mm(in.)A
Permissible Thickness Variation,mm(in.) Size1B Size2C Size3D
0.75(0.030)+0.178(0.007)E NA F NA F
−0.229(0.009)
1.0(0.039)+0.152(0.006)E NA F NA F
−0.254(0.010)
1.25(0.049)+0.152(0.006)E NA F NA F
−0.254(0.010)
1.5(0.059)+0.381(0.015)+0.610(0.024)NA F
−0.483(0.019)−0.686(0.027)
2.0(0.079)+0.356(0.014)+0.559(0.022)NA F
−0.508(0.020)−0.711(0.028)
2.5(0.098)+0.330(0.013)+0.533(0.021)NA F
−0.533(0.021)−0.737(0.029)
2.5(0.100)+0.330(0.013)+0.533(0.021NA F
−0.533(0.021)−0.737(0.029)
3.0(0.118)+0.381(0.015)+0.508(0.020)+0.762(0.030)
−0.635(0.025)−0.762(0.030)−1.02(0.040) 3.2(0.125)+0.381(0.015)+0.508(0.020)+0.762(0.030)
−0.635(0.025)−0.762(0.030)−1.02(0.040) 3.8(0.150)+0.406(0.016)+0.559(0.022)+0.737(0.029)
−0.762(0.030)−0.914(0.036)−1.27(0.050) 4.0(0.157)+0.406(0.016)+0.559(0.022)+0.737(0.029)
−0.762(0.030)−0.914(0.036)−1.27(0.050) 4.5(0.177)+0.432(0.017)+0.559(0.022)+0.686(0.027)
−0.838(0.033)−0.965(0.038)−1.09(0.043) 4.8(0.187)+0.432(0.017)+0.559(0.022)+0.686(0.027)
−0.838(0.033)−0.965(0.038)−1.09(0.043) 5.5(0.217)+0.508(0.020)+0.635(0.025)+0.737(0.029)
−1.02(0.040)−1.14(0.045)−1.27(0.050) 5.56(0.220)+0.508(0.020)+0.635(0.025)+0.737(0.029)
−1.02(0.040)−1.14(0.045)−1.27(0.050) 6.0(0.236)+0.508(0.020)+0.635(0.025)+0.508(0.030)
−1.02(0.040)−1.14(0.045)−1.27(0.050) 6.4(0.250)+0.508(0.020)+0.635(0.025)+0.737(0.029)
−1.02(0.040)−1.14(0.045)−1.27(0.050) 7.9(0.312)+0.559(0.022)+0.686(0.027)+0.813(0.032)
−1.22(0.048)−1.35(0.053)−1.47(0.058) 8.0(0.315)+0.559(0.022)+0.686(0.027)+0.813(0.032)
−1.22(0.048)−1.35(0.053)−1.47(0.058) 9.0(0.354)+0.635(0.025)+0.762(0.030)+0.889(0.035)
−1.40(0.055)−1.52(0.060)−1.65(0.065) 9.5(0.375)+0.635(0.025)+0.762(0.030)+0.889(0.035)
−1.40(0.055)−1.52(0.060)−1.65(0.065) 12.0(0.472)+0.635(0.025)+0.762(0.030)+0.889(0.035)
幽默搞笑−1.65(0.065)−1.78(0.070)−1.91(0.075) 12.7(0.500)+0.635(0.025)+0.762(0.030)+0.889(0.035)免费在线
−1.65(0.065)−1.78(0.070)−1.91(0.075) 15.0(0.591)+0.737(0.029)+0.737(0.029)+0.864(0.034)
−1.80(0.071)−1.80(0.071)−1.93(0.076) 15.9(0.625)+0.838(0.033)+0.838(0.033)+0.965(0.038)
−1.96(0.077)−1.96(0.077)−2.08(0.082) 16.0(0.630)+0.838(0.033)+0.838(0.033)+0.965(0.038)
−1.96(0.077)−1.96(0.077)−2.08(0.082) 18.0(0.709)+0.762(0.030)+0.762(0.030)+1.02(0.040)
−2.03(0.080)−2.03(0.080)−2.29(0.090) 19.0(0.750)+0.762(0.030)+0.762(0.030)+1.02(0.040)
−2.03(0.080)−2.03(0.080)−2.29(0.090) 22.0(0.866)+0.660(0.026)+0.660(0.026)+1.17(0.046)
−2.13(0.084)−2.13(0.084)−2.64(0.104) 24.0(0.945)+0.584(0.023)+0.584(0.023)+1.22(0.048)
−2.21(0.087)−2.21(0.087)−2.84(0.112) 25.4(1.00)+0.584(0.023)+0.584(0.023)+1.22(0.048)
−2.21(0.087)−2.21(0.087)−2.84(0.112) 31.8(1.250)+1.32(0.052)+1.32(0.052)+1.32(0.052)
−2.39(0.094)−2.39(0.094)−2.39(0.094) 32.0(1.280)+1.32(0.052)+1.32(0.052)+1.32(0.052)
−2.39(0.094)−2.39(0.094)−2.39(0.094) 38.0(1.496)+1.00(0.039)+1.00(0.039)+1.96(0.077)
−3.07(0.021)−3.07(0.121)−4.04(0.159) 44.0(1.732)+1.24(0.049)+1.24(0.049)+2.34(0.092)
−3.48(0.137)−3.48(0.137)−4.57(0.180) 44.4(1.750)+1.24(0.049)+1.24(0.049)+2.34(0.092)
−3.48(0.137)−3.48(0.137)−4.57(0.180)
Nominal Thickness,
mm(in.)A
Permissible Thickness Variation,mm(in.)
Size1B Size2C Size3D
50.8(2.000)+1.47(0.058)+1.47(0.058)+2.74(0.108)
−3.86(0.152)−3.86(0.152)−5.13(0.202)
51.0(2.008)+1.47(0.058)+1.47(0.058)+2.74(0.108)
−3.86(0.152)−3.86(0.152)−5.13(0.202)
57.0(2.244)+1.78(0.070)+1.78(0.070)NA F
−4.22(0.166)−4.22(0.166)
64.0(2.520)+2.01(0.079)+2.01(0.079)NA F
−4.60(0.081)−4.60(0.181)
70.0(2.756)+2.34(0.092)+2.34(0.092)NA F
−4.93(0.194)−4.93(0.194)
76.0(2.992)+2.59(0.102)+2.59(0.102)NA F
−5.28(0.208)−5.28(0.208)
80.0(3.150)+2.89(0.114)+2.89(0.114)NA F
−5.64(0.222)−5.64(0.222)
90.0(3.543)+3.07(0.121)+3.07(0.121)NA F
−6.07(0.239)−6.07(0.239)
95.0(3.740)+3.40(0.134)+3.40(0.134)NA F
−6.40(0.252)−6.40(0.252)
100.0(3.937)+3.61(0.142)+3.61(0.142)NA F
−6.81(0.268)−6.81(0.268)
A Thickness of unshrunk sheet will increa approximately4%when it is heated at thermoforming temperatures.
B Sizes up to and including91by152cm(36by60in.)and102by127cm(40 by50in.).
C Sizes by larger than Size1,up to and including122by234cm(48by84in.), 135by203cm(53by80in.),and152by183cm(60by72in.).
D Sizes larger than Size2,up to and including170by259cm(67by102in.)and 183by244cm(72by96in.).
E For colorless sheet only,tolerances shall be0.356mm(+0.014in.),0.229 mm(−0.009in.)for0.762-mm
(0.030-in.)thickness and0.330mm(+0.013in.), 0.432mm(−0.017in.)for1.02mm(0.040in.)and1.27-mm(0.050-in.)thick-ness.
F Not applicable.
7.Number of Tests
7.1Perform the number of tests indicated in each test method in Section8.All of the tests listed in Section8shall be ud to establish conformity of a material to this specification. The average result for the specimens tested shall conform to the requirements prescribed in this specification.It is recom-mended that routine inspection be limited to the following: 7.1.1Thickness and dimensions,
7.1.2Appearance,and
7.1.3Deflection temperature.
8.Test Methods
8.1Determine the properties enumerated in this specifica-tion in accordance with the following test methods.All test specimens are to be prepared from sheet as received unless stated otherwi in the
specific test method,except that for Category B-2sheet,the properties listed in Table2may be determined in the resin from which the sheet is extruded. 8.1.1Test Conditions—Conduct the test in the standard laboratory atmosphere of2362.0°C(73.461.8°F)and506 5%relative humidity,unless otherwi specified in the test methods or in this specification.
8.1.2Index of Refraction—Test in accordance with Test Methods D542using the Refractometric Method.
8.1.3Specific Gravity—Test in accordance with Method A of Test Methods D792.
8.1.4Luminous Transmittance—For colorless material measure the light transmittance in accordance with Test Method D1003.The test specimens must be taken from the material as
received.
8.1.5Haze—Test in accordance with Test Method D1003, except that the test specimens shall have a thickness not over 12.7mm(0.500in.).Measure haze on colorless material only. The test specimens must be taken from the material as received.
8.1.6Water-Absorption—Test in accordance with Test Method D570using the24-h immersion procedure.Before testing,condition the test specimens for24h at5063°C(122 65.4°F).
8.1.7Shrinkage:
8.1.7.1Procedure A—For Category A-1and A-2materials, test two specimens,each300by300mm(11.81by11.81in.). On each specimen,mark twofine lines at right angles to each other entirely across the specimen from the midpoints of opposite edges.Placefine gage marks across each of the lines and5062.5mm(1.9760.1in.)from the edge of the specimen.Measure the distance between each pair of gage marks to the nearest0.25mm.Suspend each specimen from outside the gage marks at one end in a circulating-air oven at 160610°C(320618°F)for the length of time specified in the following schedule(e Note4):
Nominal Thickness,mm(in.)Heating Time,min
6.0(0.236)or less16
9.00(0.354)25
12.0(0.472)33
18.0(0.708)55
24.0(0.944)79
38.0(1.500)136
51.0(2.000)203
55.0(2.165)and greater240
After removal from the oven,allow the specimens to cool to 2361.0°C(73.461.8°F),while in the suspended position. Remeasure the distance between each pair of gage marks and calculate the shrinkage as the percent change in distance between gage marks,bad on the original distance,as follows:
%shrinkage5@~d12d2!/d1#·100(1) where:
d1=original distance,and
d2=distance after thermal conditioning.
N OTE4—For thickness falling between tho specified,u the heating time for the next higher thickness.
8.1.7.2Procedure B—For Category B-1and B-2materials, lect three150by150mm(6by6in.)areas,one near the center area of the sheet.At the approximate center of each area, scribe a line parallel to the machine direction,and a line at90°to this,to indicate the transver direction of the sheet.At the point of interction of the lines,scribe a125mm(5in.) diameter circle.Mark the scribed diameters for identification as machine or transver direction.Cut the150by150mm(6by 6in.)specimens out of the sheet.Hang the specimens in a circulating-air oven maintained at5066°C(122610°F)for a period of time equal to2h for each0.25mm(0.01in.)of sheet thickness(e Note5).Without cooling,lay the speci-mens horizontally on a piece of preheated plate glass sprinkled with talcum powder and place in a circulating air oven maintained at160610°C(320618°F).Preheat the plate glass to the test temperature in the oven for at least15min before laying the specimens on it.Heat the specimens for the period of time prescribed in the following schedule:
Nominal Thickness,mm(in.)Heating Period,
min
3.0(0.118)or thinner15
Over3.0(0.118)30 Remove the plate glass with the specimens from the oven and cool to room temperature in still air.Measure the diameters scribed on the specimen in the machine direction and in the transver direction.Report the average change in length in each direction as a percent of the original diameter,as follows:
%shrinkage5@~l12l2!/l1#·100(2) where:
l1=original length,anduw
l2=average length after thermal conditioning.
N OTE5—Sheet that has been in storage for prolonged periods may require a longer period of conditioning to avoid the formation of bubbles due to moisture.
8.1.8Thermal Stability:
8.1.8.1Procedure A—For Category A-1and A-2materials, test two sheets,each300by300mm(11.81by11.81in.).Hang each sheet in a circulating-air oven at18065°C(35669°F). Time of heating shall be1⁄2h for9.0mm(0.354)mm thickness and under,1h for above9.0mm to24.0mm(0.944in.) inclusive,and2h for over24.0mm thickness.After removal from the oven,allow the sheet to cool to2361.0°C(73.46 1.8°F)while hanging vertically.Visually examine the sheets for the prence of bubbles and blisters.
8.1.8.2Procedure B—For Category B-1and B-2materials, visually examine the specimens ud in8.1.7.2for the prence of bubbles and blisters.
8.1.9Deflection Temperature Under Flexural Load—Test in accordance with Test Method D648at1820kPa(264psi) loading.
8.1.10Tensile Strength and Elongation at Break—Test in accordance with Test Method D638,using Type I or Type II specimens at a cross-head speed of5mm/min(0.2in./min).
8.1.11Impact Strength(Izod)—Test in accordance with Method A of Test Methods D256.
8.1.12Spectral Transmittance of Type UVF and UVT Sheet—Measure the spectral transmittance at each wavelength specified in Table2with a suitable spectrophotometer.
8.1.13Abrasion Resistance—(Applicable to Finish3Mate-rial Only):
Test one specimen in accordance with Test Method D1004, using a500-g load on each wheel for100cycles.
8.1.14Coating Adhesion—(Applicable to Finish3Material Only):
Test one specimen in accordance with Section11,Tape Adhesion,of Practice D3002,except as follows:Clean the surface using isopropyl alcohol with a soft cloth and then air-dry.Make four parallel cuts3.2mm(0.125in.)apart and a similar t of cuts at90°to thefirst.Remove the debris with light hand rubbing using Grade0000steel wool,being careful not to contaminate the test area with grea or
fingerprints.
Apply a strip of 25.4mm (1.0in.)wide cellulo tape,8pressing the tape down firmly without wrinkles or bubbles.Remove the tape immediately by quickly pulling it at a 90°angle.Repeat the tape pull two times,using fresh tape each time in the same grid area,being careful not to contaminate the grid by touching it.Visually compare the area from which the coating has been removed to the standards contained in Fig.1of Test Method D 3359.地址英文
8.1.15Chemical Resistance —Test one specimen in accor-dance with the Covered Spot Test of Test Method D 1308.The three tested reagents shall be the following:(1)3%aqueous solution of trisodium phosphate,(2)40%aqueous solution of sulfuric acid,and (3)reagent-grade toluene.
9.Retest and Rejection
9.1If any failure occurs,the materials may be retested to establish conformity in accordance with agreement between the purchar and the ller.
10.Packaging and Package Marking
10.1Packaging —The material shall be packaged in stan-dard commercial containers,so constructed as to ensure acceptance by common or other carriers for safe transportation at the lowest rate to the point of delivery,unless otherwi specified in the contract or order.
10.2All packing,packaging,and marking provisions of Practice D 3892shall apply to this specification.
11.Keywords
11.1acrylic;acrylic sheet;plastic;plastic sheet;PMMA;poly(methyl methacrylate);recycled material;transparent plas-tic;sheet
SUMMARY OF CHANGES
This ction identifies the location of lected changes to this specification.For the convenience of the ur,Committee D20has highlighted tho changes that may impact the u of this specification.This ction may also include descriptions of the changes or reasons for the changes,or both.
D 4802–02:
(1)Added paragraph 1.4to address recycling.(2)Deleted paragraph 8.1.13.1and Note 6.(3)Corrected typographical errors in Table 3.D 4802–01:
(1)Revid type designation and requirements from UV Absorbing to UV Filtering to eliminate confusion with general purpo materials which contain UV absorber.
(2)Deleted exceptions for and references to corner letgoes.(3)Deleted requirements for and references to obsolete test
methods D 673and D 756.
(4)Deleted weathering requirements which only applied to finish 3material.
(5)Revid packaging requirements.
(6)Added veral nominal thickness to Table 3to accom-modate both hard metric and hard English units to clearly specify the tolerances since both are ud commercially.No tolerances were changed.
(7)Summary of Changes ction added.
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8
3M 600cellulo tape,or equivalent,has been found suitable for this
purpo.
FIG.1Maximum Percent Water Absorption Versus
Thickness
