Plastics - Phenolic resins - Determination of the gel time
1 Scope
This standard specifies two methods, i.e., method A and method B, for determining the gel time of phenolic resins at a given temperature under specified conditions. The test temperatures are 100℃, 130℃and 150℃.
Method A specified herein is applicable to liquid resols, method B is applicable to liquid resols and solid resols with low melting points.
Powdered resins with a short gel time, such as mixtures of thermoplastic resins and hexamethylenetetramine, do not lend themselves to this type of determination. Such resins crosslink as soon as fusion starts and become too viscous in the test tube to give meaningful results. Resins containing large amounts of a solvent with a low boiling point are especially unsuitable for this type of determination. With such resins, a boiling and distillation process takes place as the resin hardens.
It is of interest to determine the time taken for the resin to gel in the presence of a catalyst. The catalyst shall be added in well defined proportions. The type of catalyst used and its treatment shall be stated in the test report.
2 Method A (Manual method)
2.1 Principle
Put the reverse mouth test tube into the oil bath, and stir the liquid resols clockwise in the test tube with a stainless steel rod until the resin becomes gel.
2.2 Apparatus
2.2.1 Thermostatically controlled bath: maximum temperature 200℃; the control precision of the selected test temperature ±0.5℃. The density of the bath liquid, e.g. silicone oil, shall be 1g/cm3±0.1g/cm3.
2.2.2 Reverse mouth test tube: 10mm±0.2mm in diameter and 77mm±2mm in length.
2.2.3 Stainless steel bar: diameter 1.2mm±0.1mm; and length approx. 130mm.
2.2.4 Stopwatch: accurate to 1s.
2.2.5 Iron stand and matching test tube holder.
2.2.6 Disposable syringe.
2.3 Specimen
The specimen shall be sealed and stored at room temperature within 8h, and refrigerated at 0℃~10℃ for a long time. The specimen may be directly used for test without pretreatment.
2.4 Procedure
2.4.1 Perform the test in duplicate, or on a greater number of parallel specimens as agreed between the parties concerned.
2.4.2 The test temperature shall be 100℃, 130℃ or 150℃, as agreed between the parties concerned.
Foreword i 1 Scope 2 Method A (Manual method) 3 Method B (Automatic method) 4 Test report Annex A (Informative) Precision in ISO 9396: 1997
Standard
GB/T 33315-2016 Plastics--Phenolic resins--Determination of the gel time (English Version)
Standard No.
GB/T 33315-2016
Status
valid
Language
English
File Format
PDF
Word Count
5500 words
Price(USD)
160.0
Implemented on
2017-7-1
Delivery
via email in 1 business day
Detail of GB/T 33315-2016
Standard No.
GB/T 33315-2016
English Name
Plastics--Phenolic resins--Determination of the gel time
Plastics - Phenolic resins - Determination of the gel time
1 Scope
This standard specifies two methods, i.e., method A and method B, for determining the gel time of phenolic resins at a given temperature under specified conditions. The test temperatures are 100℃, 130℃and 150℃.
Method A specified herein is applicable to liquid resols, method B is applicable to liquid resols and solid resols with low melting points.
Powdered resins with a short gel time, such as mixtures of thermoplastic resins and hexamethylenetetramine, do not lend themselves to this type of determination. Such resins crosslink as soon as fusion starts and become too viscous in the test tube to give meaningful results. Resins containing large amounts of a solvent with a low boiling point are especially unsuitable for this type of determination. With such resins, a boiling and distillation process takes place as the resin hardens.
It is of interest to determine the time taken for the resin to gel in the presence of a catalyst. The catalyst shall be added in well defined proportions. The type of catalyst used and its treatment shall be stated in the test report.
2 Method A (Manual method)
2.1 Principle
Put the reverse mouth test tube into the oil bath, and stir the liquid resols clockwise in the test tube with a stainless steel rod until the resin becomes gel.
2.2 Apparatus
2.2.1 Thermostatically controlled bath: maximum temperature 200℃; the control precision of the selected test temperature ±0.5℃. The density of the bath liquid, e.g. silicone oil, shall be 1g/cm3±0.1g/cm3.
2.2.2 Reverse mouth test tube: 10mm±0.2mm in diameter and 77mm±2mm in length.
2.2.3 Stainless steel bar: diameter 1.2mm±0.1mm; and length approx. 130mm.
2.2.4 Stopwatch: accurate to 1s.
2.2.5 Iron stand and matching test tube holder.
2.2.6 Disposable syringe.
2.3 Specimen
The specimen shall be sealed and stored at room temperature within 8h, and refrigerated at 0℃~10℃ for a long time. The specimen may be directly used for test without pretreatment.
2.4 Procedure
2.4.1 Perform the test in duplicate, or on a greater number of parallel specimens as agreed between the parties concerned.
2.4.2 The test temperature shall be 100℃, 130℃ or 150℃, as agreed between the parties concerned.
Contents of GB/T 33315-2016
Foreword i
1 Scope
2 Method A (Manual method)
3 Method B (Automatic method)
4 Test report
Annex A (Informative) Precision in ISO 9396: 1997
