I have trained myself to not check email first thing in the morning or the first thing I do when I turn on my computer or iOS devise. Responding to someone's email, whether that is simply opening it and reading it or by typing up a response, is working on someone else's agenda. Instead, I have disciplined myself to work on other things. Things that honestly are more important.
As a side benefit, by getting to emails second or third on my list of to-do's for the day, I have less emails to deal with in general. Hoping a quick reply will deal with the issue can often lead to the very opposite: a response with more particular demands.
Email replies should not be instantaneous. If you want instantaneous, try texting or phoning. Emails should be responded to in the time I decide to take. That maybe two hours or two days. I am okay with that. I will often type up a response and let it sit in the hoper. Then I will come back around, re-read it, make revisions, and then finally send it.
Remember email communication is not likely your most productive task of the day. It will be on your list of to-do's, no doubt. But leave it down the list of tasks.