I've been using silicone and sulphate free shampoo and conditioner for around 3 or 4 weeks now. My hair feels dryer, which I did kind-of expect with the loss of coating and product build up, but now when I use hair straighteners, even on a low heat setting, the section of hair I've just straightened (or attempted to curl) hardens into a solid section, which I then have to brush out.
Do I just need to stick it out? Does it take a while for the condition to improve? I wash my hair around 3 or 4 times a week.
I think what happens with long term silicone use and the high heat from straighteners is that the silicone becomes bonded to the hair. Usually a heat protector is used which is normally silicone based so gives the illusion of smooth hair follicles but is just adding to the problem. There may be a work around. Hopefully someone can give you some info.
If you use sulfate and silicone-free shampoo and conditioner, your styling products and anything else touching your hair must also be silicone free, otherwise there are no sulfates to wash them out (this is the gimmick behind clarifying shampoo). You get a thick coating of them on your hair within a short time.
I'd go back to using silicone if I was you! I love the stuff and it makes my hair look and feel a million times better. It's possible to avoid build up by stripping out the silicone every 10 days or so with Vosene shampoo or similar.
I don't think silicone is the bad guy for everyone- it depends on your hair type. Going silicone free definitely helps if you're wearing your hair curly. IME, the results of using straighteners is greatly improved by using silicone products- each strand is coated which will protect your hair from heat damage and give a smoother shinier result.
Have you been using extra conditioner? If your hair isn't coated (or coated as much as you've still been using one product) but you're still using straighteners then you're going to be drying it out a bit.