Mail Merge Print Protected PDF

Hi.

I need to used Word's Mail Merge to send personalized documents that need to have printing disabled.

I usually have to generate them, open them one by one, change properties, save, manually add them to an email and send them.

Some days ago the documents were generated with password protection enabled. I had to send another document without password protection and the configuration got lost.

How can I specify that all new PDFs converted from Word have to have printing disabled and be Password Protected?

Thanks.

Armando.