Q: Is it okay to turn research articles into a book?

All the options you are considering, including a couple more we will suggest, are fine to do, because your understanding of how you should go about them is fine: you are basing newer writings on your dissertation rather than aiming to publish them as is. So long as you follow this principle, you should quite safely be able to avoid self-plagiarizing.

So, it’s fine to write more journal articles based on a topic in your dissertation. As you have already written one, you would know how to go about doing this. Nevertheless, you may refer to this resource for additional insights: Tips on rewriting your thesis as a journal article

It’s also possible to write a book based on one or more topics in your dissertation. However, a book, as you may understand, is a slightly different – and bigger – creature. Plus, there are other factors at play. Either you pitch a book idea (with a couple of chapters) to a publisher (actually, a commissioning editor), who if interested, may greenlight it. Of course, they will make edits (or ask you to do so) as needed. At times, an interested publisher or editor may come across your article/s in a publication and approach you to work out a book based on one or more themes in the article. In this case, as you can understand, while the germ may come from the dissertation, you will have to do a lot more writing to flesh it out into a book.

You could also have considered publishing your dissertation as a monograph (through a university, academic, or scholarly publisher), but the opportunity for that may now be past as you have already published one article based on your dissertation.

Finally, and this will eventuate over time, you could regularly submit and have pieces published in journals and other publications with scientific leanings, which are then compiled or anthologized into a book by a publisher. This, as you may understand, involves building significant academic cred, though of course over time.

Hope that helps. And all the best with all that writing! :-)

Speaking of which, as you seem to have quite a bit of flair with words (evident in your largely impeccably framed query), you may consider writing in a couple of spaces we provide. One is our Researchers and Their Stories section, where researchers and academics share narratives (quite often personal) around various aspects of the researcher and scholarly life. You may find out more here: Researchers and Their Stories The other is our Guest Contribution section, through which you can contribute a piece on a research or scholarly topic of interest or expertise. You may find out more here: Write for Us

Related reading:

• How should I go about writing a book based on my published article?
• How to write a book review
• "Book reviews perform an important function for authors, readers, and the discipline as a whole."