I think these two terms are so distinct. theoretical framework means the background and somehow the whole literature of a variable, for example innovation.

In the other hands, conceptual framework means a figure which can depict the relationship between two variables which originates from theoretical framework. In simpler words, if we assume a house, theoretical framework is like foundation of the house and the whole building which is constructs on the foundation and we can see it as house is conceptual framework.

agree with Saeid Nosrati

it depends on use.

these are also broad/ loose terms.

i would see conceptual framework to be broader and less defined than a theoretical framework.

i would also liken conceptual framework with paradigms, and so forth.

within a paradigm, there are many possible theories, that subscribe to the paradigm.

the theories of contending paradigms would then differ or 'clash' too.

both quantitative and qualitative studies subscribe to, and can be analyzed in terms of their paradigms/ conceptual frameworks.

in many wasys, particularly in terms of methodology, the paradigms/ conceptual frameworks of qualitative and quantitative studies differ.

Kate Abraham

In harmony with Brian Barnard 's and Saeid Nosrati 's answers, the purpose of presenting the theoretical framework is to clearly identify the hypothesis and reflect on the theory after data collection and analysis whether it is confirmed or disconfirmed. In addition, theoretical framework provides and depicts theories that explain why the current research problem exists. However, I think that your research paradigm determines the role of theory in the research. You must consider your world view in the research; epistemology, ontology and axiology.

In conceptual framework section the fundamental concepts that characterize and delineate the study variables is presented to establish an informed understanding of the study field.