A Surface-Reactive Rod-Coil Diblock Copolymer:  Nano- and Micropatterned Polymer Brushes

Abstract

A diblock copolymer consisting of poly(3-(triethoxysilyl)propylisocyanate) (PIC) and polystyrene(PS) was synthesized by anionic polymerization. A polymeric monolayer of the block copolymer was formed on silica substrates by various grafting techniques such as immersion, casting, or contact-printing. The PIC block adheres covalently to Si substrates in an in-plane fashion due to its extended rodlike conformation and reactivity to the silica. The polystyrene blocks aggregate to form mounds on the surface resulting in a new type of nanopatterned polymer brush. The self-limiting adsorption of the rod coils results in a thickness of about 5 nm regardless of the solution concentration and coating method. This particular property allowed microcontact printing directly onto silicon or glass substrates. The resulting surface morphology consisted of nanoscale domains given by the block copolymer and uniform thickness micropatterns transferred from the stamp within the printed area. This study offers a simple new method to prepare a covalent polymeric monolayer with nano- and micropatterns, which can be performed directly onto various silicon-based substrates.

Preparation and characterization of organic-inorganic hybrid nanomaterials using polyurethane-b-poly[3-(trimethoxysilyl) propyl methacrylate] via RAFT polymerization

“…The peak was also shifted gradually to higher molecular weight and the PDI became narrower with the increase of the feed ratio of TPM ( Table 1), indicating that the RAFT polymerization occurred and the well controlled copolymers were obtained. Polyurethane prepared by condensation polymerization, as 20 Guo et al -eXPRESS Polymer Letters Vol.4, No.1 (2010) [17][18][19][20][21][22][23][24][25] Figure 2. Gel permeation chromatograms of PU and PU-PTPM copolymer precursors known, has a high PDI.…”

“…It may be ascribed to the deformation mechanism of PU [36]. In case of PU composed of hard and soft segment domains, the hard segment domain, sensitive to applied stress, can be tilted 22 Guo et al -eXPRESS Polymer Letters Vol.4, No.1 (2010) [17][18][19][20][21][22][23][24][25] Figure 5. TGA curves of PU and its nanocomposites Figure 6.…”

“…TPM with reactive trimethoxysilane groups is widely used in the preparation of organic-inorganic hybrid nanomaterials [15][16][17][18][19]. With a base catalyst, the R-Si(OCH 3 ) 3 groups can be easily hydrolyzed into R-Si(OH) 3 which can subsequently transform into cross-linked polysilsesquioxane nanocages by condensation, thus producing organic-inorganic hybrid nanoballs [7,20,21]. Recently, some research interests have sparked in the studies of self-assembly of copolymers based on poly [3-(trimethoxysilyl) propyl methacrylate] (PTPM).…”

“…">Experimental 2.1. MaterialsDibutyl tin dilaurate, 2-hydroxypropyl acrylate (HPA), methyl ethyl ketone (MEK), THF (purchased from Sinopharm Chemical Reagent Co., Ltd China), isophorone diisocyanate (IPDI, from Alfa 18 Guo et al -eXPRESS Polymer Letters Vol.4, No.1 (2010) [17][18][19][20][21][22][23][24][25] Aesar) and isophorone diamine (Fluka), 3-(trimethoxysilyl) propyl methacrylate (TPM, purchased from Acros Organics), 2,2′-Azobisisobutyronitrile (AIBN, purchased from Shanghai Shisihewei Chemical Co.) were used without further purification. Poly(diethylene adipate) (PDA, purchased from Jiangdu Longchuan Wear-Resistant Polymer Materials Co., Ltd China) was dried under vacuum at 80°C for 1 h before use.…”

Multiple Ordering Transitions: Hierarchical Self‐Assembly of Rod–Coil Block Copolymers

“…1d). [21] Polyisocyanates are stiff, helical, extended chain polymers and form lyotropic nematic liquidcrystalline solutions. [22,23] The molecular weight of the flexible coil PS block is 39 kg/mol and that of the PIC is 23 kg/mol, with a PIC weight fraction of 37 %.…”