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How Temperature Affects Viscosity

  How Temperature Affects Viscosity: Viscosity can be defined as the internal friction that occurs as a material flow, relative to itself....

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2017年12月20日星期三

Ubbelohde viscometer diameter and applicable solvent list


Capillary diameter mm: 0.37; Applicable solvents: Dioxane
Capillary diameter mm: 0.38; Applicable solvent: chloroform
Capillary diameter mm: 0.39; Applicable solvents: acetone
Capillary diameter mm: 0.41; Applicable solvent: ethyl acetate
Capillary diameter mm: 0.46; Applicable solvents: Ding Ding acetate, acetone (1: 1
Capillary diameter mm: 0.47; Applicable solvent: tetrahydrofuran
Capillary diameter mm: 0.48; Applicable solvents: n-heptane
Capillary diameter mm: 0.49; Applicable solvents: dichloroethane, toluene
Capillary diameter mm: 0.54; Applicable solvents: chlorobenzene, benzene, methanol, p-xylene, n-octane
Capillary diameter mm: 0.55; Applicable solvents: butyl acetate;
Capillary diameter mm: 0.57; Applicable solvents: dimethylformamide, water;
Capillary diameter mm: 0.59; Applicable solvents: dimethylacetamide;
Capillary diameter mm: 0.61; Applicable solvents: cyclohexane, dioxane
Capillary diameter mm: 0.64; Applicable solvents: ethanol;
Capillary diameter mm: 0.66; Applicable solvents: nitrobenzene
Capillary diameter mm: 0.705; Applicable solvents: cyclohexanone
Capillary diameter mm: 0.78; Applicable solvents: o-chlorophenol, n-butanol
Capillary diameter mm: 0.80; Applicable solvents: phenol, tetrachloroethane 1: 1;
Capillary diameter mm: 1.07; Applicable solvent: m-cresol

2017年11月22日星期三

Using Ubbelohde viscometer to measure the molecular weight of polyacrylamide

Test Method: Use 85g / L sodium nitrate solution will be configured as a dilute solution sample, with Ubbelohde viscometer to determine the ultimate viscosity, according to empirical formula to calculate the molecular weight of the sample.

Reagent solution: 85g / L sodium nitrate solution
Equipment: Ubbelohde viscometer (capillary diameter 0.55mm)
Constant temperature water bath (can control 30 ℃ ± 0.1 ℃)
Stopwatch (division 0.1s)
Acid filtration funnel
The company is located in:
Experimental steps:
1. Determination of sodium nitrate solution outflow time
The clean, dry Ubbelohde viscometer vertically placed 30 ℃ ± 0.1 ℃ constant temperature water bath so that the U-viscometer D ball all submerged under the water.
Will be filtered through acid filtration funnel sodium nitrate solution was added to the Ubbelohde viscometer filling line between G, so far, constant temperature 10min-15min.
M tube set a hose, with the clip, use the ear ball to the sodium nitrate solution into the D ball half, remove the ear wash ball, open the M tube.
Measure the time it takes for the sodium nitrate solution to flow through the timed markers E, F with a stop watch. Repeated determination of three times, the error does not exceed 0.2s, whichever is the average t0.
2. Preparation of sample solution
Weigh 0.03 g of solid sample or equivalent amount of colloidal sample from a known 50 mL dry beaker to the nearest 0.2 mg and dissolve with sodium nitrate solution. All transferred to 100mL volumetric flask, diluted with sodium nitrate solution to the mark, shake.
3. Determine the outflow time of the sample solution
The outflow time t1 of the sample solution is determined by the first step method
4. Calculate the result according to the formula


Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
Skype: kenyuan9023   Wechat/WhatsApp:+86 15068109723lei@zonwon.com  www.zonwontech.com
    

2017年11月14日星期二

Using Ubbelohde viscometer one-point method to determine the intrinsic viscosity


Material: a triangular flask
Two 10ml pipettes
Ubbelohde viscometer (capillary 0.5mm)
A water bath (temperature control accuracy of ± 0.1 ℃)
A stopwatch
Rubber hose two sections
A syringe
Wash the ear ball one
The company is located in:
step:
1, the system solution: Take a certain amount of polymer, add 10mm solvent, make it completely dissolved, if necessary, heated.
2, constant temperature: installed device, stable temperature up and down changes 0.1 ℃.
3, plus the solution balance 5min: up and down into the capillary tube three times.
4, determination: measured three sets of data, so that the deviation but 0.2s.
5, Determination of solvent flow time.


data processing:
ηr = t / t0 (t is the solution flow time, t0 solvent time)
ηsp = ηr-1
[η] = [2 (ηsp-ηr)] / C (C is the concentration unit g / ml)
[η] = (ηSP / C) c = 0 = (ln ηr / C) c = 0 [η] = KMα
Remove the pipette has been pre-heated solution 10ml, into the viscometer, the same method, the installation of viscometer, the determination of the solution outflow time t. Then followed by adding 2.00,3.00,5.00,10.00 ml of distilled water.


Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
Skype: kenyuan9023   Wechat/WhatsApp:+86 15068109723lei@zonwon.com  www.zonwontech.com
    

2017年10月25日星期三

The average molecular weight of macromolecules was measured with a dilution type Ubbelohde viscometer

The average molecular weight of macromolecules was measured with a dilution type Ubbelohde viscometer
1. Diluted Umbrella viscometer, only suitable for those who dissolve the sample, that is, add a certain volume dilution, the sample is easy to dissolve again, without stirring and so on.
2. Water-soluble samples are more suitable for dilution-type black capillary viscometer, organic phase, especially relatively viscous DMF solvent, not suitable for dilution capillary viscometer.
3. dilution of the viscosity of the pipe itself there is an error, generally used for production enterprises quality inspection, such as: chemical fiber plants, etc., require faster, not so accurate all the situation.
4. Scientific research is more suitable for non-dilute type, especially similar to DMF and other viscous solvents.
5. With the Ubbelohde viscometer to measure the average molecular weight of the polymer can refer to the empirical formula (polyester, nylon are applicable), M = (relative viscosity -1) × 10500.
6. Measure several points, that is, more than a few different concentrations of time.
7. With non-dilution capillary test, if the test time is abundant, and the same type of capillary has several roots, or can guarantee the capillary viscometer clean, then you can measure several different concentrations of time, so with more Point extrapolation method to calculate the intrinsic viscosity, and more accurate.
8. The tester should prepare the sample solution in advance, in particular, to ensure that the sample solution dissolved fully, completely, in line with the requirements of the standard method, and the concentration is known, accurate!

Do the same viscosity test and do GPC test the same place, that is, to dissolve the sample to be sufficient, complete, otherwise the data is not accurate. This is why dilution-type capillaries are limited because the dilution capillary itself is smaller than the non-dilution type, but is still relatively small, at least not suitable for dissolving those solvents that are viscous or have a very high intrinsic viscosity Samples, such as polyolefin samples, polyacrylamide samples are typical, too much viscosity, it is not suitable for dilution capillary. In addition, the exact dilution of the concentration, for the dilution of the capillary, it is also a problem. Due to the small size, a little error in the operation may cause the concentration to be inaccurate.

Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
 /Wahtsapp: +86 15068109723  lei@zonwon.com 
 

    

2017年10月10日星期二

Introduction and influencing factors of kinematic viscosity determination of petroleum products

Scope of application
The petroleum product movement tester is designed and manufactured according to the national standard GB/T265. It is used to measure the kinematic viscosity of liquid petroleum products. LCD screen Chinese display, man-machine dialogue interface, preset temperature, test time and other parameters menu prompt input, appearance design is beautiful, is the introduction of new instruments.
Viscosity is one of the main indexes of petroleum products, and viscosity is one of the important factors that affect the biodegradability of base oils. Many domestic lubricants are classified and classified according to their kinematic viscosity of 40oC and 100oC. In practical application, viscosity is an important index to evaluate the flow performance of lubricating oil. It is important for quality identification of petroleum products and their application. Viscosity is large, oil film thickness is large, lubrication performance is good, but the viscosity is too large, will increase the friction resistance, waste of resources.
Kinematic viscosity is the ratio of the dynamic viscosity of a liquid to its density at the same temperature. It represents a measure of the friction of a liquid when it flows under gravity. Kinematic viscosity measurement is the determination of the time at which a certain volume of liquid passes through a calibrated glass capillary viscometer at a constant temperature. The product of the capillary constant and flow time, i.e., the kinematic viscosity of the liquid at this temperature.

Functional characteristics
1. ring type fluorescent lamp illumination, fluoroscopy is good. Easily observed.
2. heater and guide tube and bath parts are made of stainless steel, durable and durable.
3. Automatically calculate the capillary constant and the average product of the test time. The temperature control precision is high and the accuracy is good.
4, computer temperature control, timing, constant temperature, water bath and other parts. Constant temperature bath is small cylinder, round cylinder, double layer, uniform temperature distribution in the bath, the temperature control effect is good.
5. Chinese LCD screen display, man-machine interface, the preset temperature, test time and other parameters, menu input, actuator adopts advanced SSR, its features of no contact, no spark, no action noise, vibration resistance, long life.

Technical parameter:

1, weight: 25kg
2, constant temperature accuracy: + 0.1
3, the number of cards installed capillary: 3 branches
4 ,heater power: 1000W
5, environmental temperature: room temperature to 35 degrees
6, temperature control settings: room temperature to 100 degrees set at any time
7, work power supply: 220V + 10% 50Hz
The main factors influencing the determination of kinematic viscosity:
First, the measurement of the factors:
1. Stopwatch: The stopwatch is used to determine the time the sample flows through the viscometer. If the stopwatch is not precise enough, it may cause a test error. Therefore, for the use of the stopwatch, be sure to regularly test.
2. viscometer coefficient: capillary viscometer must be calibrated on a regular basis, otherwise it will cause a greater error.

Second, the experimental operation of the factors
1, the viscosity of the process of measuring the flow of oil through the viscometer
The flow time of the specimen must be within the specified range. GB / T265 provides that the flow time to> 200S. Mainly in order to ensure that the oil flow in the viscometer for the laminar flow. If the oil flow rate is too fast beyond the specified range, will become turbulent, with turbulence can not use the cassace equation to calculate the viscosity of oil. In addition, the flow rate is too fast, the reading error will increase accordingly. If the oil flow rate is too slow, within a specified time is not easy to maintain constant temperature
2, the viscosity of the test process bath temperature accuracy
Determination of kinematic viscosity to be strictly in accordance with the provisions of constant temperature test, which is the determination of oil moving viscosity of one of the important conditions. In GB / T265, the temperature control accuracy of the thermostatic bath must be ± 1oC, while in the ASTMD445 bath temperature control accuracy of ± 0.5oC. Because the viscosity of the oil sample decreases with increasing temperature and increases with the temperature drop, it must be strictly in accordance with the specified constant temperature, the slight temperature deviation will make the viscosity measurement results have a greater error.
Third, the viscosity of the other factors in the determination process
Test oil samples containing impurities, moisture and capillary viscometer is not washed, will also affect the sample in the capillary viscometer in the normal flow, the results are high. The solvent used for the washing in the viscometer is not dry and the sample is diluted so that the result is low.
When measuring the viscosity of the oil, the sample in the viscometer can not have air bubbles. If the oil bubbles will affect the oil volume, while entering the capillary will form a gas plug, so that the flow resistance of oil increased, the determination of high results.


Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
 /Wahtsapp: +86 15068109723  lei@zonwon.com 
 

    

2017年8月7日星期一

K, α value of Some Common Polymer

K, α value of Some Common Polymer 

Abstract:
Polymer, Polymerization Method, Molecular Weight Range, Solvent Temperature K Value, Polystyrene (PS) Solution Polymerization 3-1700 Toluene 25 ° C 1.7 0.69 1-11 Benzene 25 ° C 4.17 0.60 5.9-5.2 Benzene 20 ° C 1.23 0.72 330-Benzene 30 ° C 1.1 0.73 polymethylmethacrylate bulk polymerization 70-6300 benzene 25 ° C 0.468 0.77 (PMMA) 240-4500 benzene 25 ° C 0.38 0.70 emulsion polymerization 410-3400 acetone 25 ° C 0.96 0.69 410-3400 toluene 25 ° C 0.71 0.73 410-3400 Chloroform 25 ° C 0.34 0.83 styrene-butadiene rubber (SBR) emulsion polymerization 25-500 toluene 25 ° C 5.25 0.66 emulsion polymerization 50 ° C 26-1740 toluene 30 ° C 1.65 0.73 emulsion polymerization 5 ° C 55-1000 toluene 30 ° C 2.95 0.75 natural rubber (NR) 0

Polymer
Polymerization Method
Molecular Weight Range
Solvent
Temperature
K Value
α Value  
Polystyrene (PS)
solution polymerization
3-1700
Toluene
25 ° C
1.7
0.69


1-11
benzene
25 °C
4.17
0.60


5.9-5.2
benzene
20 ° C
1.23
0.72


330-
benzene
30 ° C
1.1
0.73
Poly (methyl methacrylate) PMMA
Polymerization
70-6300
Benzene
25 ° C
0.468
0.77


240-4500
benzene
25 ° C
0.38
0.70

Emulsion Polymerization
410-3400
Acetone
25 ° C
0.96
0.69


410-3400
Toluene
25 ° C
0.71
0.73


410-3400
Chloroform
25 ° C
0.34
0.83
Styrene-butadiene rubber (SBR)
emulsion polymerization
25-500
Toluene
25 ° C
5.25
0.66

Emulsion Polymerization 50 ° C
26-1740
Toluene
30 ° C
1.65
0.73

Emulsion Polymerization 5 ° C
55-1000
Toluene
30 ° C
2.95
0.75
Natural rubber (NR)

0.4-1500
Benzene
25 ° C
5.02
0.17

Butadiene rubber (BR)

20-1300
Toluene

25 ° C
2.15
0.65


26-660
Butanone
30 ° C
4.8
0.55
Polyacrylonitrile (PAN)

48-270
Dimethylformamide
25 ° C
1.66
0.81
Polyester (PET)

  3-370 
Dimethylformamide
25 ° C  

2.33
0.75


12-28
Phosphorus Chlorobenzene
25 ° C  
3.0
0.77


 5-25
phenol / tetrachloroethane
25 ° C
2.1
0.82
Polyvinyl alcohol (PVA)

11.6-195
Water
25 ° C
5.95
0.63


44-1100
Water
50 ℃
5.9
0.67


30-120
Water
30 ℃
6.6
0.64


Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
 /Wahtsapp: +86 15068109723  lei@zonwon.com 
 

    

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