polymer-chemistry

## What I do - Study polymer synthesis and characterization - Analyze polymer structure-property relationships - Research polymer physics and mechanics - Develop new polymer materials - Investigate polymer processing - Study polymer degradation and stability ## When to use me - When synthesizing polymers - When analyzing molecular weight - When studying polymer properties - When designing polymeric materials - When investigating polymer processing - When researching biodegradable polymers ## Key Concepts ### Polymerization Methods **Step-Growth** - Condensation polymerization - Requires difunctional monomers - Molecular weight increases slowly - M_n ~ 1/(1-p) **Chain-Growth** - Free radical, ionic, coordination - Rapid molecular weight build-up - Active center propagation ```python # Example: Degree of polymerization def degree_of_polymerization(conversion, functionality): """ Calculate X_n for step-growth. conversion: p (0-1) functionality: f (functionality) """ return 1 / (1 - conversion) # Molecular weight distributions def number_average_mn(degree_polymerization, monomer_mw): """M_n = X_n × M_0""" return degree_polymerization * monomer_mw def weight_average_mw(degree_polymerization, monomer_mw, mw_dist): """M_w = Σ(N_i × M_i²) / Σ(N_i × M_i)""" # Polydispersity index: PDI = M_w/M_n return degree_polymerization * monomer_mw * mw_dist ``` ### Polymer Properties - Glass transition temperature (Tg) - Melting temperature (Tm) - Crystallinity - Molecular weight (Mn, Mw) - Polydispersity index - Mechanical properties ### Important Polymers - Polyethylene (PE): Packaging - Polypropylene (PP): Automotive - Polystyrene (PS): Insulation, foam - Polyvinyl chloride (PVC): Construction - Polyethylene terephthalate (PET): Fibers, bottles - Polytetrafluoroethylene (PTFE): Non-stick