Polyethylene Functionalization

../_images/02funcPE3.png

This modifier functionalizes polyethylene (PE) by replacing selected CH2 units with CO, ester, or amide groups. The functionalization can be random (percentage-based) or periodic (fixed spacing along the backbone). End-group carbons are excluded.

Functionalization types

  • CO replaces CH2 with a carbonyl group.

  • ``COH``replaces CH2 with a hydroxy group.

  • ester replaces CH2-CH2 with COO.

  • amide replace CH2-CH2 with CONH.

Modes

  • Random mode selects a target number of CH2 sites based on the requested percentage and then chooses positions at random while respecting the neighbor_exclusion to keep functional groups separated. A neighbor_exclusion value of three means, that between two functional groups are at least three untouched CH2 units.

  • Periodic mode places functional groups at a fixed interval along the backbone using the provided distance (m). A distance of three means, that between two functional groups are three untouched CH2 units. For the CO, ester and amide functionalization types, a functionalized polymer stand can look like this:

../_images/02funcPE4.png

Command line

-funcPE random:percentage:func_type:neighbor_exclusion
--functionalizePE
Random functionalization of PE by replacing CH2 groups with func_type.
percentage is a float from 0 to 100.
neighbor_exclusion is the minimum C-C hop distance between functional groups.

-funcPE periodic:distance:func_type
--functionalizePE
Periodic functionalization along the backbone.
distance is the spacing between functional groups (integer >= 1).
func_type is CO, COH, ester, or amide.

-funcPE-file
--functionalizePE-file
Output filename.
Default: functionalizedPE.xyz

Example

MakroLyzer -xyz PE.xyz -funcPE random:15:CO:2 -funcPE-file PE_CO.xyz
MakroLyzer -xyz PE.xyz -funcPE periodic:6:ester -funcPE-file PE_ester.xyz

Note

  • Chain-end carbons (with only one carbon neighbor) are excluded from functionalization.

  • For ring polyethylene, the distance criterion might not be met for two adjacent functional groups per ring.

Output

An XYZ file containing the modified structure.