programs halted when change IP. connections sshfs

[Seon]

All ubuntu distribs !

I have script for connect to remote server by ssh (see attachment file ssh-connect.sh)
If I establish connection for server, I may normally work with remote directory through file managers (like nautilus, thunar or PCManFM) and text editors (like geany)

If my internet connection was broken, I must reboot my router and this change my IP
After that all programs which use my ssh connection are halted.
I can not close it any way.
Directory where I have connection to remote resource, broke too.

I am try use:
killall -SIGKILL sshfs
umount -l <mouted-dir>

But if I try reistablish connection, file managers still halted when I open new mounted connection.

Thereafter I can not reistablish connection and can not disconnect broken connection.
Most easy way for fix this - reboot system.