HG/T 2234-1991 Determination of viscosity of polycarbonate dilute solution
Some standard content:
Chemical Industry Standard of the People's Republic of China
HG/T2234-91
Determination method for viscosity of dilute solutions of polycarbonate Issued on December 27, 1991
Ministry of Chemical Industry of the People's Republic of China
Implementation on July 1, 1992
Chemical Industry Standard of the People's Republic of China
Determination method for viscosity of dilute solutions of polycarbonate This standard is equivalent to the international standard ISO1628/.4-1986 "Plastics - Carbonate molding and extrusion materials"
Subject content and scope of application
This standard specifies the conditions for determining the viscosity of dilute solutions of polycarbonate, HG/T2234--91
Determination of viscosity and intrinsic viscosity
This standard is applicable to polycarbonate homopolymers, copolymers and their mixtures. May or may not contain filler. Reference Standards
GB1632 Determination of viscosity and intrinsic viscosity of dilute polymer solutions 3 Definitions and units
Definitions and units can be found in Chapter 2 of GB1632.
Viscosity number VN is expressed in mL/g.
In the formula:
(n-ng)
dynamic viscosity of the solution, pas;
dynamic viscosity of the solvent, pas
density of the solution, kg/m
po—density of the solvent, kg/m
(vp-vop.)
YoPopt
kinematic viscosity of the solution (v=n/p), m/ss—kinematic viscosity of the solvent (=ne/po), m/so
concentration of the polycarbonate solution, g/mL
Note: Since the density difference between the solution and the solvent is very small, the kinematic viscosity is used instead of the dynamic viscosity in formula (1). 4Measurement
Measurement shall be made according to Chapter 3 of GB1632.
Approved by the Ministry of Chemical Industry of the People's Republic of China on December 27, 1991, Part 4: Poly
Implementation on July 1, 1992
Where: k viscometer constant, mm2/s2
Flow time, s;
HG/T2234-91
At-—kinetic energy correction time (△t=A/kt), s; density, kg/m2
Note: Different from Chapter 3 of GB1632, the kinetic energy correction time At can only be ignored when it is less than 0.002t. 5 Instrument
See Chapter 4 and Table B1 of GB1632.
5.1 Capillary viscometer: OC type or 2-036 type suspension Ubbelohde capillary viscometer in GB1632, capillary inner diameter 0.36mm, measuring ball volume 2mL.
Other viscometers can be used as long as they can get the same result, but this type of viscometer must be used in case of dispute. The calibration of the viscometer used shall be carried out according to Appendix A1, 5.2 Timer: readable to 0.1s, rate stability within 15min is ±0.1%. 5.3 Constant temperature bath: can be maintained at 25±0.05℃. 5.4 Volumetric flask: with ground glass stopper, 100mL, 5.5 Balance: accurate to 0.1mg,
5.6 Drying oven: can be maintained at 110℃.
5.7 Petri dish,
5.8 Filter glass funnel: No. 2,
5.9 Fritted glass funnel: No. 3.
5.10 Oscillator,
Centrifuge.
6 Reagents and solutions
See Chapter 5 of GB1632.
6.1 Reagents
Dichloromethane, redistilled, boiling range 39~41℃, refractive index 1.423~1.4256.2 Sampling
The sample should reflect the characteristics of the material being tested
6.3 Solution concentration
Each liter of solution contains 5g of resin
6.4 Solution preparation
6.4.1 Polycarbonate without filler
Weigh 0.5±0.01g of sample (accurate to 0. 1mg), placed in a 100mL volumetric flask, add about 70mL of dichloromethane, stir to promote its dissolution, place in a constant temperature bath at 20±1℃, then dilute to the scale with 20±1% dichloromethane or weigh the solvent to make the concentration reach 0.5g/100mL, shake well for use, for materials containing pigments or special additives, the weighing should be increased so that every 100mL solution contains 0.5g of polycarbonate. Note: ① When the content of pigments or additives is higher than 0.5% (m/m), calibration must be carried out (in most cases the pigment content is less than 0.5%). Soluble dyes and pigments below 0.5% (m/m) do not hinder measurement. ② To prevent the solution with high pigment content from dirtying the capillary, it can be treated according to 6.4.2, and diatomaceous earth filter material or centrifuge can be used to remove these additives.
6.4.2 Polycarbonate with filler
HG/T2234-91
Weigh about 5g of sample, place in a round-bottom flask, add about 70mL of dichloromethane, and dissolve it under continuous stirring. To ensure complete dissolution, the sample can be crushed first.
When the filler (such as glass fiber) is precipitated, filter the solution into a culture dish with a No. 3 sintered glass funnel. Evaporate the solvent in a fume hood to form a film, and place the film in an oven at 110℃ to constant weight (1 to 10 hours, depending on the thickness of the film). Prepare the dry film into a solution according to 6.4.1
7 Measurement temperature
The measurement temperature is 25±0.05℃,
8 Test steps
See Chapter 3 of this standard and Chapter 7 of GB1632. Filter dichloromethane into the viscometer through a fritted glass funnel, measure its flow time 3 to 5 times at 25±0.05℃, take the arithmetic mean, the flow time range does not exceed 0.01%, repeat the above operation with the sample solution,
9 Calculation of test results
See Chapter 8 of GB1632.
Calculate the viscosity number according to the following method, mL/g,
Calculate according to Appendix A3.
b. Calculate according to formula (3):
Where: y
. -At
kinematic viscosity of a solution, m2/s:
Vokinematic viscosity of the solvent, m2/s;
flow time of the solution, s;
to—flow time of the solvent, s;
concentration of a solution, g/mL;
At is the kinetic energy correction time of the viscometer when the flow time provided by the manufacturer is s; Ata is the kinetic energy correction time of the viscometer when the flow time provided by the manufacturer is S.Ata
Note: This formula is based on GB1632 but introduces the kinetic energy correction time. For a viscometer of a specific size, in order to obtain accurate results, it is necessary to calculate
in routine inspection. If a viscometer with a sufficiently small capillary inner diameter is used, the kinetic energy correction time is less than 0.2% of the flow time. In routine inspection, a result of similar accuracy can be calculated from formula (10) in GB1632: VN-
To verify the kinetic energy correction time △1 and △fo, see Appendix A1 and A2 respectively. Test report || tt||See Chapter 9 of GB1632,
HG/T2234-91
HG/T2234—91
Appendix A
Calibration Procedure
(Supplement)
A1 Verification of Viscometer Accuracy
Experience has shown that the high accuracy required for determining the viscosity of polycarbonate solutions cannot always be obtained from commercially available Ubbelohde viscometers due to small irregularities in the capillary. It is therefore recommended to verify the accuracy of the measurement with the aid of a calibration liquid of known kinematic viscosity. The following liquids are recommended:
8. Dichloromethane (analytical pure) = 0.3142mm2/s, Pg = 1.3163g/mL; b. Trichloroethylene (analytical pure) y = 0.3693mm2/s, P, = 1.4555g/mL; c. Tetrachloroethylene (analytical pure) v2 = 0.5257mm2/s, P2 = 1.6144g/mL. Note: The above values are all at 25.00℃. Measure the flow time of these liquids through the viscometer at 25±0.05℃ for 3 to 5 times to determine the kinetic energy corrected flow time. The flow time range does not exceed 0.1%.
Calculate the viscosity ratio according to formula A1:
t, -At,
t. At.
V2t,-At
t. -At.
Compare the measured value with the following "correct\value": 1.175
Their deviation should not be greater than 0.4%,
A2 Determination of effective capillary constant ker and kinetic energy correction time Ater If the difference between the expected value and the measured value of the viscosity ratio of the calibration liquid is greater than 0.4%, the effective capillary constant ke and kinetic energy correction time Ater
should be determined according to the following method. The arithmetic mean obtained from the following three formulas is the effective capillary constant keny
k,- (,-Ar,)
(k。+k, +k,)
Where:
HG/T2234-91
The calibration reduction body recommended in Chapter A1 (respectively the kinematic viscosity of mouse or): - the corresponding flow time;
The kinetic energy correction time provided by the viscometer manufacturer. Calculate the effective kinetic energy correction time according to formula (A9): At
The obtained value is plotted against the corresponding flow time A1. Use the interpolation method to obtain the corresponding effective kinetic energy correction time 41
Aftier
Flow time
A3 Simplified calibration method
The relationship between the flow time and viscosity ratio of a viscometer that does not meet the requirements of A1 can be directly measured with the help of a calibration liquid. This calibration is independent of the information of the capillary constant and the kinetic energy correction. For a certain viscometer, the viscosity ratio v/ and y/v of the calibration liquid are plotted against the measured flow time t and. For the viscosity ratio of a polycarbonate solution with a concentration of p, the interpolation method can be used to obtain the flow time 1 point in Figure A2, and the viscosity number is calculated according to formula (A10):
Note: Formula (A10) is the same as formula (3).
Additional remarks: bzxz.net
HG/T2234-91
Flow time
This standard is proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Chemical Method Branch of the National Plastics Standardization Technical Committee. This standard was drafted by the Shanghai Synthetic Resin Research Institute. The main drafter of this standard is Li Jun,
People's Republic of China
Chemical Industry Standards
Determination of viscosity of dilute solutions of polycarbonate HG/T2 234—91
Editor: Chemical Industry Standards Editorial Department
(Standardization Research Institute of the Ministry of Chemical Industry)
Postal Code: 100013
Printer: Standardization Research Institute of the Ministry of Chemical Industry
Copyright reserved. No reproduction allowed
Format: 880×12301/16
5 Words: 11000
Printing Times
First Edition in November 1992
First Printing in November 1992
Printing Quantity: 1—500
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