The first step is to create a schema based on the data that will be used to populate the adaptive form.
Use the schema to create your adaptive form
You can use any of the free online tools to generate XSD from the xml data generated in the previous step.
Create an adaptive form based on the schema from the previous step.
It is always recommended to examine the data that is generated on the Adaptive Form submission. This will give you a good idea of the XML format of the data that needs to be merged with the adaptive form.
Data submitted from Adaptive form
Data exported from the PDF
Form the exported data, you will have to extract the topmostSubform node with the appropriate namespaces preserved for successfully merging data with the adaptive form.