Save money times, the price point of polyether continues to climb.
It is fortunate to witness more than ten years of rigid foam products from profiteering to thin profit, raw materials from Li Kui metamorphosis into the process of Li Ghost. While sighing at the creativity of imitation of our compatriots, it is better to write something, so as not to bear the suspicion of “behind the slander”.
The following things in advance: please don’t take the right place, not to mention imitation, as we all know: I have a unique eye, see things are double.
[View]: 1. The appearance of polyether should be transparent, regardless of color shades.
If translucent or opaque, be careful, most have problems. First take the raw material barrel at different locations in the material samples to see if there is no layering, it is best to check the bottom of the barrel, to see if there are particles of sediment and so on. This situation can only explain: ①, polyether production control is not good, the reaction did not react; ②, polyether post-processing work is not done; ③, mixed with the money-saving things.
In August this year, Zh.Y’s 4110 polyether three batches are not transparent, even if the sample is taken out overnight to delaminate itself, the preparation of the combination of materials is also the same, and the height of delamination is more than 10%, it seems that the technical level of blending needs to be improved.
2, polyether color is too dark estimated that we generally do not have a good feeling, at least that the production of polyether starting agent did not “pull enough vacuum” or hanging epoxy propane (PO) when the temperature is too high. Even if the polyether color deep, it should be brownish red, if there is an abnormal “greenish (greenish some)”, beware: in my impression, only rosin polyester and aromatic diamine polyether will have this look, do not worry, aromatic diamine polyether is too expensive, no one for you to mix in.
3, if the polyether viscosity is significantly larger than before (shake or tilt the polyether packaging bottle can be seen), very good: no need to call you can determine the price of PO, and this year’s bumper crop of cane sugar, polyether manufacturers to help you throw some PO, and he will probably be kindly explained as: increase the hardness in order to resist shrinkage
[Sniff]: The normal sugar-containing starting polyether has a caramel “fishy” smell.
1, if there is a strong smell of ammonia, PH test paper before the mouth of the barrel becomes “10”, nine times out of ten contains urea.
2, if there is a “fragrance” similar to turpentine, it is definitely a product of the northeast direction. (403 and other amine ether is not included in this)
[Wash]: Most of the hard foam polyether can stick to the hands with tap water to rinse clean.
Washing does not depend on the range of its hydroxyl value is how much: below 380mgKOH / g can still understand (or can be washed, just not so smooth), higher than 380 should not have to use soap.
If the laundry detergent can not be washed once, it must be a green product (tar modified polyol, terpene alcohol fat, rosin polyester, modified soybean oil, castor oil, PTA polyester, etc. are difficult to wash, as for the phenolic polyol —– price is too high to do and trouble fools to add it)
[Comparison experiments]: the most convincing is the foaming comparison experiments, the following is the most commonly used 4110 as an example
Want to see the situation of polyether B, then take the usual quality of trustworthy polyether monomer A as a reference, first depending on the use (for example: insulation) to design a formula based on composition
A B
Polyether 100 100
Silicone oil 1.5 1.5
Water 1.0 1.0
Cyclohexylamine 1.2 1.2
141B 27 27
(Note: The sample bottles should be of the same size and type)
1, all with the weight of × 2, first compared to the appearance of transparent (above suitable for 25-28 ℃ environmental state), opaque reasoning as before.
2, the left and right hands each grab a material sample bottle together, to ensure that the liquid level on both sides of the same level, flush chest flat, and then together before and after the shock: see who “jumped high” on both sides, so you can roughly determine the viscosity of high and low.
3, the same conditions as the above to perform foaming (black / white 1.05/1, stirring 6 seconds, before and after the successive foaming do not exceed 10 minutes, to be poured into a plastic bag hanging), record the respective time (milky white, drawing, not sticky hands), and according to the foam in the plastic bag.
And according to the height of the bubble body in the plastic bag to determine roughly whether the density is a big difference. If the difference between the foaming time of A and B polyether is too big (more than 2 seconds for milky white, more than 5 seconds for drawing, more than 7 seconds for non-sticky hand), then “add some cyclohexylamine and water to the slow one according to the remaining amount to make it faster and higher” and re-foam it, and try to adjust their foaming speed and size to make no difference. After the bubble body are not sticky hands 3min after sent to 20 ℃ in the air-conditioned room natural “maturation” 15min
4, in principle, polyether polyol (such as 4110) is the starting agent to hang propylene oxide (PO), the capping end is “secondary hydroxyl”, so its activity should not be high, if the object of investigation polyether compared to the “very saving” catalyst, there is more than 90% If the object of investigation is polyether, it is more than 90% sure that it has “active hydrogen” component.
5, look at the foaming process of rising whether there is “fried bubble” phenomenon (against the light and stare at the surface of the bubble “bright” area to see whether there is a burst of explosive points, like fried mines).
If there is, it means that the bubble body of the bubble pore must not be fine enough, or at least “eat silicone oil”. The reason, most of the polyether production used in the epoxy propane (PO) aldehyde content is high, may also be the polyether by hydrocarbon oil contamination (for example, the packaging barrel is not washed), and then the polyether is mixed with grease polyol.
6, look at the appearance of the bubble body whether there is a cross-line shrinkage. Low-functionality polyol (such as castor oil, phthalic anhydride polyester, rosin polyester, glycol, etc.), high hydrocarbon chain structure (modified vegetable oil polyol, etc.) will cause cross-line shrinkage, the more powerful shrinkage means that the skeleton is not hard enough, cross-linking points are not enough, the degree of functionality is not large enough.
7, pinch the edges whether there is brittle powder phenomenon. Glycerin-doped powder brittle the most aggressive, rosin polyester second, urea third, the market phthalic anhydride, benzene polyester and some varieties of modified vegetable oil is not good enough to go, used in the infusion of insulation “bonding” will not be good. In addition, PO connected to less, hydroxyl value is large, the foam body will also have brittle powder aggravation (crispy skin) phenomenon.
8, look at the upper part of the foam body whether there is an obvious “drawing traces”, combined with the residual foam in the foam cup “out of the cup mouth is round and smooth” can be judged roughly the polyether foam is “good fluidity “. Now some polyether factories do not mix things, but unfortunately to improve the “yield” is not post-processing, more annoying is to throw some glacial acetic acid down and neutralize potassium hydroxide is done, in fact, equivalent to adding potassium acetate in the polyether, the liquidity is not “good”.
9, foam body 20 ℃ after maturation can be cut, compared to the appearance of the bubble hole and measure the density, especially pay attention to the side of 1.5mm under the skin whether there is a “thick hole corridor”, if there is, that polyether first do not use: the money earned is not enough to run to deal with quality accidents on the road.
10, compared to the surface of the foam body (the part of the positive surface in contact with the air) whether the bubble hole is fine and has a sense of smoothness, too rough, most of the bubble hole is not suitable for cooperation with high-density imitation wood products.
[Destruction test]
The following test temperature 25-28 ℃ best
1, if the above comparison test is not too clear to see, take some time to engage in damage.
A B
Polyether 100 100
Silicone oil 0.8 0.8
Water 2.0 2.0
Cyclohexylamine 1.2 1.2 (add or subtract as appropriate, adjusted to material speed flagging)
141B 20 20
Carbon tetrachloride 5 5
All the fractions into x 3, the first bubble to leave the bottom, the rest of the material samples in the sun during the day and into the 35-40 ℃ oven at night. So that within 5 days to see the appearance of which color first darkened, and then foaming to see the slow speed of the material, as well as the destructive situation of the silicone oil. It is not difficult to judge the advantages and disadvantages.
2、 Polyether with imitation spray coating
Polyether 100
Silicone oil 1.5
Water 0.7
A-33 2.5
T-12 0.3
Am-1 1.0
141B 18
Perform 60g/60g (black/white) foaming and see if there is any heartburn (yellow heart). Pure polyether will not cause heartburn in this system.
[Other tests and instructions]
1. 403 test.
403 100
Silicone oil 1.0
141B 30
Direct 1/1 foam, should be set in 35 seconds
2、Other auxiliary polyether
According to different uses try to design a reasonable ratio to test.
For example, the Northeast “365” itself low hydroxyl value, viscosity is small, in the white material can only be used as an auxiliary polyether, then it is arranged in the main polyether accounted for 40% of the test; Another example is 303, 210
It is also necessary to let it take up a small proportion of the test.
Like 635, 835, 1050 and so on can do the main polyether, but the hydroxyl value is high, then the appropriate increase in the proportion of black and white material foam test to go, the specific calculation of the basis of future exchange column and then discuss in detail.
3, miscibility test.
If the samples into the test itself is auxiliary type, the first step is instead “miscible”: 100ml beaker, according to the design ratio.
100ml beaker, pour down the main and auxiliary polyether (ester) in the designed proportion of 50 grams, stir well with a small glass rod to see if it is transparent; then add the proportion of silicone oil, water, catalyst, physical blowing agent stir well to see if it is still transparent. If this does not work, pour the mixture into a test tube and store it for at least 24 hours at rest (with a seal) to see its storage stability. For example, high bridge 330N can be added to the ordinary imitation wood at least 10% not delamination, while some manufacturers of even 3% can not add —- this is the gap.
