https://doi.org/10.1351/goldbook.09587
Regular macromolecule having a configurational repeating unit comprising four configurational base units, the first two stereogenic units of which are identical and enantiomorphic to the last two.
Notes:
- A macromolecule consisting only of m and r diads in alternating sequence (i.e. mr and rm triads) is heterotactic. The configurational repeating unit consists of four configurational base units.
- The prefix ht- is recommended to indicate a heterotactic macromolecule.
- A heterotactic polypropylene can be depicted by a rotated Fischer Projection (top) and zigzag projection (bottom) as follows. The configurational repeating unit, a mrm tetrad, is shown within brackets. The configurational repeating unit can be equally well defined as a rmr tetrad.
Source:
PAC, 2020, 92, 1769. 'Definitions and notations relating to tactic polymers (IUPAC Recommendations 2020)' on page 1776 (https://doi.org/10.1515/pac-2019-0409)
PAC, 2020, 92, 1769. 'Definitions and notations relating to tactic polymers (IUPAC Recommendations 2020)' on page 1776 (https://doi.org/10.1515/pac-2019-0409)