Children should be prioritised for sure.
But as for women, no. All this rubbish about men having a better chance of surviving the conditions because they are 'physically stronger' than women (funny how this suddenly becomes a unanimously accepted truth when we're talking about sinking ships but is vehemently denied if someone suggests women require men to look after them in everyday life or in potentially dangerous situations etc) is exactly that, rubbish. A person's physical strength will have very little impact on their survival chances if we're using the Titanic scenario as an example. I don't care if Leonardo DiCaprio was 6'7" and built like a Mexican wrestler, he still wouldn't have survived in those temperatures for that long.
The best way I can think to explain it is like this:
Here is a scale from 1-10.
1-----2-----3-----4-----5-----6-----7-----8-----9-----10
Say that your physical state has to be at least 9 on the scale in order for you to survive. Let's say that children are at number 2 on the scale. Women are at number 5 (because apparently now we're all conceding that they are so much more physically frail than men) and men are at number 7, for the same reason. But although the men are further towards the survival threshold of 9 on account of their 'superior physical strength', and thus technically have a better chance of surviving the situation than women, they in effect do not have a better chance at all because the supposed difference in physical strength between the genders is insufficient to make such a difference as to allow men to survive where women would not.
Sorry if that was convaluted but it is the best way I can think to explain it.
There is not one logically valid reason why women should be prioritised over men in this situation.