i had a similar question about this because i ordered a rosemary and horsetail oil online and later saw this ingredient in it. i did some research. this has a different structure than other silicones. the structure makes it bigger so that it cannot be absorbed into hair. it basically acts as a carrier and facilitates the good natural oils making their way into the hair. after it has done its job, it evaporates since it sits on the hair's surface rather than being absorbed.
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