For the ones that is hosted on your own server and you embed the flipbook within your site, you can use dFlip PDF FlipBook jQuery Plugin.
It is flash free. Costs only $29 for regular license with 6 months customer support. You can create 3D or 2D flipbooks easily with this plugin. Additionally it has awesome page rolling effect.
The company I work for has this (paid) SDK.
See this online demo
You can use the command line tool, docx2pdf to batch convert word documents to pdf on Windows or macOS: https://github.com/AlJohri/docx2pdf
pip install docx2pdf
Disclaimer: I wrote this tool.