Problem in pull out process animating

Hello,

I have a problem in animation of pulling out a polymer chain and be tankful if guid me. As you see in the attached picture,i have fixed a group of atoms  of a polymer chain, and then i have stretched them to pull out the whole chain from the bulk. The attached picture is 5 snapshpts of total trajectories. Would you please guide me how i can animate these pulling process without having these stretch bond of fixed atoms. Because its animations and snapshots are not proper for article or presentation.

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Best Regards

SJN