Block copolymer-based nanocomposite

Of course, nanocomposites are not the only area where mesoscale theories are being used to predict nanostructure and morphology. Other applications include—but are not limited to—block copolymer-based materials, surfactant and lipid liquid crystalline phases, micro-encapsulation of drugs and other actives, and phase behavior of polymer blends and solutions. In all these areas, mesoscale models are utilized to describe—qualitatively and often semi-quantitatively—how the structure of each component and the overall formulation influence the formation of the nanoscale morphology. 

Ren, J., SUva, A. S., and Krishnamoorti, R., Linear viscoelasticity of disordered polystyrene-polyisoprene block copolymer based layered-silicate nanocomposites. Macromolecules, 33, 3739-3746 (2000). 

In this section, two examples of the use of self-nucleation are presented for block copolymers and nanocomposites. The first example shows how self-nucleation can help separate the coincident crystallization of a double crystalline diblock copolymer. In the second example, the efficiency scale based on self-nucleation helps to define supernucleation. 

Commercial membranes for CO2 removal are polymer based, and the materials of choice are cellulose acetate, polyimides, polyamides, polysulfone, polycarbonates, and polyeth-erimide [12]. The most tested and used material is cellulose acetate, although polyimide has also some potential in certain CO2 removal applications. The properties of polyimides and other polymers can be modified to enhance the performance of the membrane. For instance, polyimide membranes were initially used for hydrogen recovery, but they were then modified for CO2 removal [13]. Cellulose acetate membranes were initially developed for reverse osmosis [14], and now they are the most popular CO2 removal membrane. To overcome state-of-the-art membranes for CO2 separation, new polymers, copolymers, block copolymers, blends and nanocomposites (mixed matrix membranes) have been developed [15-22]. However, many of them have failed during application because of different reasons (expensive materials, weak mechanical and chemical stability, etc.). 

Figure 1.21 Nanocomposites based on block copolymer generated by atom transfer radical polymerization. Reproduced from Ref [45] by permission from Elsevier.

The data of paper [5] for nanocomposites based on the isotactic industrial PP (Shell Co.), filled by Na -montmorillonite with last contents cpy=0.025, 0.050 and 0.10 were used. As modificators dioctadecyldimethyl ammonium bromide (DODAB) plus block-copolymer polyethyleneoxide-polyethylene (PEO-PE) (conventional sign of nanocomposite PP-NC-1) PEO-PE (PP-NC-2) DODAB plus PEO-PE with isobutylene (PP-NC-3) PEO-PE plus isobutylene (PP-NC-4) are used. The detailed description of specimens preparation methodics is cited in the paper [5]. 

Pedroni LG, Araujo JR, Felisberti MI, Nogueira AF (2012) Nanocomposites based on MWCNT and styrene-butadiene-styrene block copolymers effect of the preparation method on dispersion and polymer-filler interactions. Compos Sci Technol 72 1787-1492... 

Zhu et al. studied polyurethane foams from soy reinforced with cellulose microfibers. They found an increase on the onset degradation temperature of the thermal degradation of polyurethane with the addition of 2 wt % cellulose fibers. They attributed this fact to the insulator effect of cellulose fibers [52]. Navarro-Baena et al. studied shape memory PU based on PLA-PCL-PLA block copolymer and reinforced with both CNCs and PLA grafted CNCs [72]. Aside the increment on the shape memory behavior of the polyurethane-based nanocomposites, they reported an increase on the thermal stability of the PU matrix in particular, they reported that, although CNCs improved the thermal stability of both PCL and PLEA blocks, in particular the thermal stability of the PCL block was improved in the nanocomposites increasing the maximum degradation temperature of about 40 with respect to the PCL block of the neat PU-matrix [72]. 

The existence of a low frequency tan 5 maximum has been reported in block copolymers[l-7], but disregarding an interpretation based on the restriction of the polymer chain mobility. However, the research of our group [8-11] considers the hindering effect of nanoparticles on the polymer chains mobility of nanocomposites, as well as the restriction to global chain motion imposed by micro or nanophases in self assembled block copolymers. 

Bone-biomimetic nanocomposite materials based on peptides potentially aimed at orthopedic applications are rather seldom reported a thermoreversibly gelling block copolymer conjugated to HA-nucleating peptides, however, has been reported similar... 

Rheology of Organoclay Nanocomposites Based on Block Copolymer... 

Henning S, Adhikari R, Borreck S, Buschnakowski M, Michler GH. Micromechanical smdies of styrenic block copolymer blends-based nanocomposites. Macromol Symp 2013 327 85-93. 

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