Plastics - Phenolic resin powder - Determination of flow distance on a heated glass plate
1 Scope
1.1 This standard specifies a method for the determination of the flow distance of powdered heat-setting phenolic resins for production and control. With reference to tablet formation, test temperature and angle of inclination of the glass plate, measurement of the flow distance involves defined conditions.
1.2 The flow distance is dependent on the reactivity and melt viscosity of the resins. Rapid solidification and high melt viscosity shorten the flow distance.
2 Principle
Tablets are first produced under defined conditions and are placed on a glass plate which has been heated to (125±1)℃ in a naturally ventilated oven. The plate, with the tablets on it, is kept in the oven for 3min in the horizontal position and then for 20min in a tilted position. The flow distance is then measured.
3 Apparatus
3.1 Oven with natural ventilation, capable of maintaining a temperature of (125±1)℃. Use a spirit level to check that it is horizontal. The temperature shall be measured in the immediate vicinity of the test tablets.
3.2 Cylindrical tablet press, for producing tablets (12.5±0.3)mm in diameter and (4.8±0.2)mm thick.
3.3 Balance, accurate to 1mg.
3.4 Tilting device, made of metal, which can position the glass plate horizontally or be manipulated from outside to position the glass plate at an angle of (60±1)° (see Figure 1).
Key
1——resin tablet; 3——metal support;
2——glass plate; l——flow distance.
Figure 1 Tilting device
3.5 Glass plate, of a suitable size to fit in the oven, for example length 100mm to 150mm, width 60mm to 120mm, thickness 2.7mm to 3mm. The glass plate shall be absolutely clean, smooth and without scratches. To make sure that the tablets have not become displaced during the test, a starting line shall be drawn on the plate.
Note: The starting line is scored on the plate using a glass cutter. It has no influence on the result, and is simply used for precise positioning of the tablets and for measuring the flow distance.
3.6 Straight steel ruler, with division value of 1mm.
4 Procedure
4.1 In cases of dispute, dry the sample in a desiccator until constant mass is obtained, for example by storing the powdered resin in a desiccator for at least 48h over phosphorus pentoxide.
Foreword i
1 Scope
2 Principle
3 Apparatus
4 Procedure
5 Expression of results
6 Precision
7 Test report
Standard
GB/T 32688-2016 Plastics一Phenolic resin powder—Determination of flow distance on a heated glass plate (English Version)
Standard No.
GB/T 32688-2016
Status
valid
Language
English
File Format
PDF
Word Count
3500 words
Price(USD)
100.0
Implemented on
2017-1-1
Delivery
via email in 1 business day
Detail of GB/T 32688-2016
Standard No.
GB/T 32688-2016
English Name
Plastics一Phenolic resin powder—Determination of flow distance on a heated glass plate
Plastics - Phenolic resin powder - Determination of flow distance on a heated glass plate
1 Scope
1.1 This standard specifies a method for the determination of the flow distance of powdered heat-setting phenolic resins for production and control. With reference to tablet formation, test temperature and angle of inclination of the glass plate, measurement of the flow distance involves defined conditions.
1.2 The flow distance is dependent on the reactivity and melt viscosity of the resins. Rapid solidification and high melt viscosity shorten the flow distance.
2 Principle
Tablets are first produced under defined conditions and are placed on a glass plate which has been heated to (125±1)℃ in a naturally ventilated oven. The plate, with the tablets on it, is kept in the oven for 3min in the horizontal position and then for 20min in a tilted position. The flow distance is then measured.
3 Apparatus
3.1 Oven with natural ventilation, capable of maintaining a temperature of (125±1)℃. Use a spirit level to check that it is horizontal. The temperature shall be measured in the immediate vicinity of the test tablets.
3.2 Cylindrical tablet press, for producing tablets (12.5±0.3)mm in diameter and (4.8±0.2)mm thick.
3.3 Balance, accurate to 1mg.
3.4 Tilting device, made of metal, which can position the glass plate horizontally or be manipulated from outside to position the glass plate at an angle of (60±1)° (see Figure 1).
Key
1——resin tablet; 3——metal support;
2——glass plate; l——flow distance.
Figure 1 Tilting device
3.5 Glass plate, of a suitable size to fit in the oven, for example length 100mm to 150mm, width 60mm to 120mm, thickness 2.7mm to 3mm. The glass plate shall be absolutely clean, smooth and without scratches. To make sure that the tablets have not become displaced during the test, a starting line shall be drawn on the plate.
Note: The starting line is scored on the plate using a glass cutter. It has no influence on the result, and is simply used for precise positioning of the tablets and for measuring the flow distance.
3.6 Straight steel ruler, with division value of 1mm.
4 Procedure
4.1 In cases of dispute, dry the sample in a desiccator until constant mass is obtained, for example by storing the powdered resin in a desiccator for at least 48h over phosphorus pentoxide.
Contents of GB/T 32688-2016
Foreword i
1 Scope
2 Principle
3 Apparatus
4 Procedure
5 Expression of results
6 Precision
7 Test report
