In general, we recommend that the amount of silicone oil is 1.5 to 3.0% of the total amount of polyether + polyester. According to different seasons, different uses to make appropriate adjustments. You use the real 100% silicone oil plus 0.5 parts will not collapse the foam, but the combination of materials generally will not be used immediately after the preparation. Especially in summer, there are always some side reactions in the process of storage to make the combination of material quality decline, the higher the temperature, the faster the reaction speed. So it is generally recommended to add silicone oil to 2% of polyether + polyester. Silicone oil ratio of more than 5% of polyether + polyester, we believe that there is no meaning (unless you use the effective content of silicone oil only 30 ~ 50%) silicone oil amount is too large, the combination of material performance has not much effect on the improvement, although the bubble hole slightly so a little subtle changes, but will affect the bonding force and other properties, the real good silicone oil do not have to add too much! Some people have done experiments on the amount of silicone oil in the combination of material on the fine density of the pores.
Silicone oil dosage on the impact of the bubble hole structure
The amount of silicone oil is adjusted according to the actual situation, different regions, different climates, different seasons, different uses have different empirical data. For example, the winter temperature is low, the foaming speed is slow, the bubble hole is easy to become thick, we recommend that silicone oil to add more, the summer is hotter can be appropriate less; hair flame retardant foam, because the flame retardant is easy to cause broken bubble, silicone oil should also be appropriate more; low density foam, silicone oil should be more, high density can be less; large block bubble, silicone oil more, a little less on the small block; refrigerator material silicone oil amount of large appropriate a little, insulation pipe less; cold storage Spraying silicone oil content to be higher, if the roof spraying a little less; with good quality polyether (such as high bridge of), polyester silicone oil less add a little also not a big problem, if the use of 20% cheaper than the market price of polyether, polyester, but also used the underground factory F-11, silicone oil even more add can not guarantee that no problem, let alone less add. We generally believe that: silicone oil up to 5% of the amount of polyether (plus polyester), not less than 1%. Different foam engineers have their own set of empirical data, which needs to be summarized and concluded in the work.
Problems that tend to occur in the use of silicone oil
Turbidity: When the weather is particularly cold or hot, some silicone oil will become turbid, this is not necessarily a problem with the quality of silicone oil, you can ask the manufacturer what the reason is, generally in the specific temperature range of silicone oil it will not become turbid. At room temperature, if the silicone oil becomes clear and does not stratify after shaking, it means that the silicone oil is fine, if it cannot become transparent, it is likely that the silicone oil has deteriorated;
Silicone oil failure: the current structure of silicone oil is relatively stable, in the shelf life of the general will not fail. Such as failure, not necessarily the silicone oil itself out of condition, there may be problems with the external environment, thus destroying the silicone oil, so that the silicone oil failure, the common problems are the following.
① The high value of cyclopropyl in polyether and polyester. Polyether, polyester, the last process to take off the cyclic propylene, such as cyclic propylene off is not clean, cyclic propylene will make the silicone oil broken chain, so that the silicone oil failure.
② F11, 141b acid is too strong. As F11, 141b is too acidic, and there are small molecules, which may destroy the silicone oil.
③ Machine oil. If your equipment leaks oil, so that the oil into the combination of material system, will also make the silicone oil destruction, which will cause large holes, and even collapse bubble
④ Polyester, organotin. Polyester with organotin as catalyst or with organotin as foaming catalyst can also make silicone oil failure, thus causing large holes, or even collapse bubble
Delamination, become smelly. Silicone oil stored in improper environment for a long time or contaminated with other impurities will decompose and become smelly when layered, such silicone oil has the effect of breaking the foam and cannot be used.
Storage and transportation of silicone oil and its use
Silicone oil should be stored in a dry and cool environment;
If stored for a long time, it is best to roll it on the ground for a minute or two before use;
After opening the barrel, if you don’t use it all at once, make sure to tighten the cap after taking the material;
Silicone oil is a non-toxic, non-corrosive silicone surfactant and is not a hazardous material. Most varieties of silicone oil are easily soluble in water, but some special varieties may not be easily soluble in water and may be soluble in alcohols; if it sticks to the skin, don’t be too nervous, just wash it with water; if it splashes in your eyes, flush it with water and see a doctor; silicone oil should not be used as food for hunger, and you should wash your stomach if you eat it by mistake;
In winter it is too cold, some silicone oil varieties will be cloudy, or even lumpy, it is best to bake to room temperature and roll evenly after use;
The shelf life of silicone oil: reasonable preservation of not less than one year. After long-term storage of silicone oil, if the physical properties of indicators are normal, the test can also be used, our company more than five years of silicone oil by the test does not affect the use.
Take a small amount of silicone oil must use a clean special apparatus. Strong acid, strong alkali or organic tin have a destructive effect on silicone oil, if you mix the utensils with such substances, it is likely to deteriorate the whole barrel of silicone oil.
The current state of the silicone oil market
Although there are no more than ten manufacturers producing silicone oil, the current market is quite confusing. There is no uniform standard for quality. There are at least some basic standards and testing methods for raw materials such as polyether and blowing agents, but silicone oil only has its own standards for each manufacturer. There is no unified standard, the quality is also uneven, and the price varies greatly. Cheap and polyether 4110 price may be about the same, expensive seventy to eighty dollars a kilogram also.
I can tell you here, the price of hard foam silicone oil in 25 to 50 yuan / kg is more reasonable, because the cost is there, believe it or not it is there! How can a real silicone oil as an additive be about the same price as 4110? The most basic silicone raw materials are in more than 30 yuan, plus transportation, processing, how much to make some money to do silicone oil! Catalyst has 4110 price? Some people say that the silicone oil we use is very cheap, very cheap silicone oil I advise you to think about why silicone oil can be so cheap, why?
We are all factories, when your customers say I use other’s combination material than your company’s cheaper 2000 yuan, how will you think? You will certainly think this combination material inside is not all glycerin ah or castor oil ah or ……… Adding polyester is not even cheaper!!! Some people say I use people’s cheaper stuff, it’s okay anyway. But I still hope that when you use cheap silicone oil, add 0.5 parts of silicone oil in 60 ℃ baked 5 days after foaming and more expensive silicone oil to compare the changes in the bubble hole, and then determine whether there is a difference between the two silicone oil. Under normal circumstances adding 2 parts of silicone oil may not be a problem, but we must prevent unexpected situations. A better silicone oil, the dosage can be lowered a little, and the benefit is the same for the combination material factory. Some people say, I dare not add less, add less for fear of problems, then you add more cheap silicone oil you are sure to add more silicone oil, not necessarily!!! Add less dare, but you dare to add cheap silicone oil!!!
Cheap vegetables, nine out of ten is gutter oil fried; cheap rice is likely to be added plastic particles; cheap noodles may be added talcum powder. I don’t know if you believe it or not, I do!
Comprehensive above.
1. silicone oil in the combination of materials or foaming process is a key additive, not much, the role is not small, no silicone oil is to collapse the bubble, silicone oil failure is also to collapse the bubble.
2. The quality and price of silicone oil is related, a price is worth a penny, you want to buy meat with the price of tofu, the possibility is very small, you are smart, others are not stupid.
3. The role of silicone oil: emulsification, nucleation, stable foam, flow.
4. The choice of silicone oil, in the purchase of silicone oil must indicate your purpose, silicone oil manufacturers can help you choose the right product according to your requirements and the characteristics of their products.
5. Silicone oil test: Silicone oil test is best to use the reduction method to do application experiments, so that it is more representative, the apparent physical properties of indicators can not represent the actual role of silicone oil.
6. The amount of silicone oil: polyether + polyester 1.5-3.5%, our company’s silicone oil we generally recommend the amount of 1.5-2.5%;
7. combination of materials such as problems do not rush to conclusions, do not say it must be a problem with silicone oil. To carefully analyze, I suggest that each engineer to develop a good habit, each time the raw materials to come with a clean apparatus to seal the sample. This way, even after the problem, you can take out the sealed samples to analyze one by one, or find the problem but can not find the root cause, which is not anxious to die! Before you ship, their own products should also be made to leave samples to observe the stability, customers have complaints can also analyze the reasons.
