Researchers are allowed to use copyrighted material in their research under the concept of "fair dealing" as long as it does not unreasonably harm the interests of the copyright owner. Consent is not required in these circumstances.
There are two ways researchers have to contend with copyright when conducting individual research The first way is when researchers use another person's ideas in their own research. In these circumstances the researcher must acknowledge in their work the source of their ideas. See DBS Referencing Guide linked here for more detail or the Copyright and Other Intellectual Property Law Provisions Act 2019 which is linked below.
The second way you may have deal with copyright regarding individual research concerns copying other persons material. While the amount of material that can be copied is not specified in law, it is recommended to follow good practice guidelines listed below:
Note: Fair dealing refers to individual researchers therefore although it is not explicitly stated it is unlikely it permits sharing multiple copies of something.