Well-Tailored Norbornene-Based Fluorinated Copolymers toward Modulating Icephobicity and Mechanical Robustness

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Science

Background:

• Developing icephobic surfaces with both mechanical robustness and tunable properties is crucial.
• Existing icephobic surfaces often lack mechanical integrity or are limited by low modulus.
• Understanding molecular structure-property relationships is key for advanced material design.

Purpose of the Study:

• To design and fabricate novel norbornene-based fluorinated polyolefin copolymers (FPOR-x).
• To investigate the structure-property relationships, focusing on mechanical and icephobic characteristics.
• To achieve robust icephobic surfaces with tunable properties by controlling soft and hard segment ratios.

Main Methods:

• Synthesis of FPOR-x copolymers via living ring-opening metathesis polymerization (ROMP).
• Utilized norbornenyl dodecafluoroheptyl ester (NDFHE) as soft segments and norbornenyl pentafluorophenyl ester (NPFPE) as hard segments.
• Characterized mechanical properties (tensile strength, elastic modulus, elongation) and ice shear strength.

Main Results:

• Tunable mechanical properties were achieved, with tensile strength from 0.2 to 26.4 MPa and elastic modulus from 0.6 to 593.7 MPa.
• The ratio of soft NDFHE content directly correlated with mechanical property variations.
• FPOR-25% exhibited a low ice shear strength of 57.7 kPa, alongside a tensile strength of 12.0 MPa and elastic modulus of 227.5 MPa.
• Synergistic interplay between soft and hard segments influenced crack propagation and reduced ice adhesion.

Conclusions:

• The study successfully established a link between polymer molecular structure and surface icephobic performance.
• The developed copolymers offer a route to robust icephobic surfaces, overcoming the modulus limitations of previous materials.
• Tailoring the soft/hard segment ratio provides a versatile strategy for designing advanced icephobic materials.