Reactive block copolymers (BCPs) provide a unique means for toughening epoxy thermosets because covalent linkages provide opportunities for greater improvement in the fracture toughness (K_IC). In this study, a tailored reactive tetrablock copolymer, poly[styrene-alt-(maleic anhydride)]-block-polystyrene-block-poly(n-butyl acrylate)-block-polystyrene, was incorporated into a diglycidyl ether of bisphenol A based epoxy resin. The results demonstrate the advantage of reactive BCP in finely tuning and controlling the structure of epoxy blends, even with 95 wt % epoxy-immiscible triblocks. The size of the dispersed phase was efficiently reduced to submicrometer level. The mechanical properties, such as K_IC, of these cured blends were investigated. The addition of 10 wt % reactive BCP into the epoxy resins led to considerable improvements in the toughness, imparting nearly a 70% increase in K_IC. The designed reactive tetrablock copolymer opened good prospects because of its potential novel applications in toughening modification of engineering polymer composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42826.

A series of gradient fluorinated copolymers with a broad variation of the monomer units in the polymer chain were synthesized via semibatch CPDB-mediated RAFT miniemulsion polymerization technique. In the presence of RAFT agent 2-cyanoprop-2-yl dithiobenzoate (CPDB), the copolymerization of BMA and FMA in miniemulsion exhibited typical features of a controlled molecular weights and narrow polydispersities. The macromolecular structure and thermal behavior of the synthesized fluorinated copolymers were investigated in detail. The DSC analyses show that the gradient copolymers showed a unique thermal behavior with broad range of transition temperature. It was also confirmed that the fluorinated gradient copolymer exhibited obvious surface segregation structure and ultra-low surface energy between 16.8 and 20.3 mN/m. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42936.

The poly(methyl methacrylate)-b-poly(2-[[[[2-(perfluorohexyl)]-sulfonyl]-amino]ehthyl] methacrylate) (PMMA-b-PC₆SMA) copolymers were successfully synthesized for the first time using activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) method. Under optimized reaction conditions, the degree of polymerization (DP) of resulting copolymers increased approximately linearly with monomer conversion. Structures of a well-defined block copolymer were determined by GPC, FT–IR, and ¹H-NMR spectra. Results from AFM and contact angle measurements of polymer films revealed the presence of block segments derived from PC₆SMA, as indicated by the obvious increase in hydrophobicity and oleophobicity. The relationship between surface composition and surface wetting ability was confirmed by XPS and AFM spectra. Compared with the random copolymer PMMA-co-PC₆SMA, C₆SMA dosages in the PMMA-b-PC₆SMA copolymers were greatly decreased, which retained its hydrophobic and oleophobic properties. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2040–2049

Novel well-defined amphiphilic fluorinated diblock copolymers P(PEGMA-co-MMA)-b-PC₆SMA were synthesized successfully by RAFT polymerization and characterized by FTIR, ¹HNMR and GPC. For copolymer coatings, static contact angles, θ, with water (θ_water ≥ 109.5^°) and n-hexadecane (θ_hexadecane ≥ 68.9^°) pointed to the simultaneous hydrophobic and lipophobic characteristics of the copolymer surfaces. Dynamic contact angle measurements indirectly demonstrated that copolymer films underwent surface reconstruction upon contact with water, which results in a surface with surface coverage of polar PEG units. Moreover, the distinct nanoscale microphase segregation structures were proved by atomic force microscopy (AFM) images. Finally, using bovine serum albumin (BSA–FITC) as the model protein, copolymers exhibited excellent protein adsorption resistance. It is believed that the combination of surface reorganization and nanometer-scale microphase segregation structure endows the excellent protein resistance for amphiphilic fluorinated copolymers. These results provide deeper insight of the effect of surface reconstruction and microphase segregation on the protein adsorption behaviors, and these amphiphilic fluoropolymers can expect to have potential applications as antifouling coatings in the field of marine and biomedical. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41167.

In this study, ammonolyzed poly(styrene-alt-maleic anhydride) terminated with dithioester group can be self-assembled into an amphiphilic macro-reversible addition-fragmentation chain transfer (RAFT) agent, and RAFT group will be located in the interface of oil and water. RAFT polymerization of styrene (S) and butadiene (B) will be confined in the interface. The main work is to study the effect of degree of aminolysis, reaction temperature, and ratio of S/B on the polymerization kinetics and living characters. The experimental results revealed that aminolysis of dithioester group would lead to retardation and loss of living characters under higher degree of aminolysis. Interfacially confined RAFT miniemulsion polymerizations were of relatively good controlled/living characters under lower degree of aminolysis before gelation. Increase of reaction temperature and ratio of S/B will accelerate the formation of gelation. Finally, styrene/butadiene copolymer nanoparticles with uniform particle size were formed, and because of microphase segregation “core–shell” morphology with polybutadiene core and polystyrene shell was seen obviously. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A series of new amphiphilic poly[methyl(3,3,3-trifluoropropyl) siloxane]-b-poly(ethyleneoxide) (PMTFPS-b-PEO) diblock copolymers with different ratio of hydrophobic segment to hydrophilic segment were prepared by coupling reactions of end-functional PMTFPS and PEO homopolymers. PMTFPS-b-PEO diblock copolymers synthesized were shown to be well defined and narrow molecular weight distributed by characterizations such as NMR, GPC, and FTIR. Additionally, the solution properties of these diblock copolymers were investigated using tensiometry and transmission electron microscopy. Interestingly, the critical micellization concentration increases with increasing length of hydrophobic chain. Transmission electron microscopy studies showed that PMTFPS-b-PEO diblock copolymers in water preferentially aggregated into vesicles. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

In this study, we conducted the reversible addition–fragmentation chain-transfer (RAFT) polymerization of styrene (St) in a miniemulsion system stabilized by two different stabilizers, ammonlysis poly(styrene-alt-maleic anhydride) (SMA) and sodium dodecyl sulfate (SDS), with identical reaction conditions. The main objective was to compare the polymerization kinetics, living character, latex stability, and particle morphology. The macro-RAFT agent used in both systems was SMA, which was obtained by RAFT solution polymerization mediated by 1-phenylethyl phenyldithioacetate. The experimental results show that the St RAFT miniemulsion polymerization stabilized by SDS exhibited a better living character than that stabilized by ammonlysis SMA. The final latices were very stable in two systems, but different stabilizers had an obvious effect on the polymerization kinetics, living character, and particle morphology. All of the particles obtained by RAFT miniemulsion polymerization stabilized by SDS were solid, but an obvious core–shell structure was observed in the miniemulsion system stabilized by ammonlysis SMA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The degradation of poly(fluoroalkyl acrylate)s with long perfluoroalkyl groups, especially with perfluorooctyl group, leads to the release of biopersistent perfluorooctanoic acid (PFOA) or perfluorooctanesulfonic acid (PFOS). To find the environmentally friendly substitutes, a series of nonbiopersistant fluorinated polymers containing perfluorohexyl groups in the side chains have been synthesized and characterized. This study was then focused on the role played by the main chain and spacer group located in the side chain between the backbone and the fluorinated segment and, in particular, on the properties of poly[2-[[[[2-(perfluorohexyl)]-sulfonyl]methyl]amino]ethyl] acrylate (PC6SA), methacrylate (PC6SMA) and poly[(perfluorohexyl)ethyl] methacrylate (PC6MA). Surface properties and bulk organization of fluorinated side chains of those polymers were investigated by contact angles, differential scanning calorimetry, optical polaring microscopy, and wide-angle X-ray scattering. Results were compared with those obtained with poly[(perfluorohexyl) ethyl] acrylate (PC6A). They all had very low surface free energies. Surprisingly, with the same perfluoalkyl chain, PC6SA and PC6SMA with a N-methylsulfonamide spacer group were found to be organized in a liquid crystalline lamellar structure, whereas PC6A and PC6MA were found to be amorphous. This was mainly attributed to the steric term and polarity of N-methylsulfonamide group that tended to facilitate the orientation of the perfluorinated segments in smectic phases. PC6SA, PC6SMA, and PC6MA had rich dynamic water repellency because of the low surface molecular mobility. This phenomenon relates to the crystallization of side chains or high glass transition temperature. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2584–2593, 2010