Polymer-ceramic nanocomposite

Windlass, H., Raj, P.M., Balaraman, D., Bhattacharya, S.K., and Tummala, R.R., Colloidal processing of polymer ceramic nanocomposites for integral capacitors, in Proceedings of the International Symposium on Advanced Packing Materials Processes, Properties, and Interfaces, IEEE, Piscataway, NJ, 2001. 

Kakimoto Masa-aki, Takahashi Akio, Tsurumi Taka-aki, et al. Polymer-ceramic nanocomposites based on new concepts for embedded capacitor. Mater. Sci. Eng. Part B. 132 no. 1-2 (2006) 74-78. 

H. Windlass, P. M. Raj, S. K. Bhattacharya, and R. R. Tummala, Processing of Polymer-Ceramic Nanocomposites for System-on-Package Application , Proceeding of2001 Electronic Components and Technology Conference, (2001), pp. 1201-1206. 

Gianuelis E P (1992) A new strategy for synthesizing polymer-ceramic nanocomposites, JOM 44 28-30. 

Novel polymer-ceramic nanocomposite membranes were fabricated, characterized, and tested for their barrier performance. Atomic layer deposition (ALD) was used to deposit alumina films on primary, micron-sized (16 and 60 pm) high-density polyethylene (HOPE) particles at a rate of 0.5 nm/cyde at 77 °C. Well-dispersed polymer-ceramic nanocomposites were obtained by extruding aluminapolymer particle size. The diffusion coefficient of fabricated nanocomposite membranes can be reduced to half with the inclusion of 7.29vol.% alumina flakes. However, a corresponding increase in permeability was also observed due to the voids formed at or near the interface of the polymer and alumina flakes during the extrusion process, as evidenced by electron microscopy [1]. 

An extensive literature survey reveals that almost all polymer-ceramic nanocomposites were prepared through mechanical blending of nanosized particles, polymer, and salt in a compatible solvent. Aggregation of these particles stemming from their high surface energy is a perennial problem that undermines the efficacy of the ceramic fillers. A simple and effective method to overcome such a problem is the sol-gel process, wherein the nanosized ceramic fillers are precipitated in situ in the polymer matrix through a series of hydrolysis and condensation reactions of suitable precursors. Thus, the ceramic fillers are uniformly distributed in the polymer and exhibit excellent properties. 

Hua F, Cui T H and Lvov Y M, Ultrathin cantilevers based on polymer-ceramic nanocomposite assembled through layer-by-layer adsorption , Nano Lett, 2004 4 (5) 823-825. 

Hybrid polymer silica nanocomposites formed from various combinations of silicon alkoxides and polymers to create a nanoscale admixture of silica and organic polymers constitute a class of composite materials with combined properties of polymers and ceramics. They are finding increasing applications in protective coatings (Figure 7.1), optical devices, photonics, sensors and catalysis.1... 

G. Ramachandian, G. Simon, Y. Cheng, and L. Dai. Control of fluorescence emission color of benzo 15-crown-5 ether substituted oUgo phenylene vinylene-ceramic nanocomposites. Polymer, 46(18) 7176-7184, August 2005. 

Chen, B. (2004). Polymer-Clay nanocomposites an overview with emphasis on interaction mechanisms. British Ceramic Transactions Vol. 103, No. 6, pg 241. 

The hybrid materials such as oxide/polymer nanocomposites can be prepared by this method. For example, the nanoscale heterogeneity can be of controlled size in metal/ceramic nanocomposites. The reduction of metal-oxides with hydrogen gives nanocomposite powders such as Fe core in the silicon oxide or Fe203 [147] and NiFc204 shell [148]. Metal particles of several nanometers size with narrow size distribution are statistically distributed in the oxide matrix without any agglomerates, as a result of binding the metal complex to oxide matrix. The narrow particle size distribution cannot be obtained if complexion of ions appears (Table 5.6). 

In the last few decades, polymeric materials have found many applications and govern a major part of our day-to-day life. The polymeric materials are strong, lightweight, and easily processable with cost-effective techniques [1]. However, the properties of the pure polymeric materials limit their application in diversified fields. The introduction of filler materials into the polymer matrix generates properties superior to those of individual components. The combination forms a single system the polymer nanocomposites exhibit improved strength, stiffness and dimensional stability with adequate physical properties compared to pure ploymer. These nanocomposites can be of different types such as ceramic-based nanocomposites, fiber-reinforced nanocomposites, polymer-clay nanocomposites, etc. 

According to the matrix, nanocomposites may be classified into three categories i) Ceramic matrix nanocomposite, ii) metal matrix nanocomposites, and iii) polymer matrix nanocomposite. In the first group of composites the matrix is a ceramic material, i.e., a chemical compoxmd from the group of oxides, nitrides, borides, silicides, etc. In most cases of ceramic-matrix nanocomposites the dispersed phase is a metal, and ideally both components, the metallic one and the ceramic one, are finely dispersed in each other in order to elicit the particular nanoscopic properties. Nanocomposites from these combinations were demonstrated to improve their optical, electrical and magnetic properties [5,4], as well as tribological, corrosion-resistance and other protective properties [6,5]. Thus the safest measure is to carefully choose immiscible metal and... 

Polymer matrix nanocomposite is the most important type of nanocomposite in which the performance of a polymer matrix can be enhanced by appropriately adding nanoparticulates to it [12] and good dispersion of the filler can be achieved [ 12]. A imiform dispersion of nanoparticles leads to a very large matrix/filler interfacial area, which changes the molecular mobility, the relaxation behavior and the consequent thermal and mechanical properties of the material. A polymer matrix could be reinforced by much stiffer nanoparticles [13,14] of ceramics, clays, or carbon nanotubes, etc. Recent research on thin films (thickness < 50 micrometer) made of polymer nanocomposites has resulted in a new and scalable synthesis technique increasing the facile incorporation of greater nanomaterial quantities [15]. Such advances will enable the future development of multifunctional small scale devices (i.e., sensors, actuators, medical equipment), which rely on polymer nanocomposites. 

Cannillo V, Bondioli F, Lusvarghi L, Montorsi M, Avella M, Errico ME, Malincceramic particles filled polymer-matrix nanocomposites. Compos Sci Technol 66(7-8) 1030-1037... 

In general, the dispersion of clay particles in a polymer matrix can result in the formation of three general types of composite materials (Figure 1). Conventional composites contain clay tactoids with the layers aggregated in unintercalated face - face form. The clay tactoids are simply dispersed as a segregated phase. Intercalated clay composites are intercalation compounds of definite structure formed by the insertion of one or more molecular layers of polymer into the clay host galleries and the properties usually resemble those of the ceramic host. In contrast, exfoliated polymer-clay nanocomposites have a low clay content, a monolithic structure, a separation between layers that depends on the polymer content of the composite, and properties that reflect those of the nano-confmed polymer. 

In recent years, the search for innovative bone substitutes for developing this new therapeutic concept has concentrated on non-metallic composite materials, particularly on polymer/ceramic composites and nanocomposites. Such (nano)composites consisting of a polymer matrix and bioactive micro/nanoflllers provide specific biomaterials for internal bone implants with biological and mechanical properties tailored for a given medical use. These materials link the advantages of polymers (structural stability, strength, biocompatibility, desired shape) with properties of ceramics that resemble those of bone structure. 

Most of the important applications of polymer-based nanocomposites have been realized in the optical area by the interesting association of the organic and inorganic components. Usually, optical composites are seen to be mixtures of a functional material and a processable matrix [49]. Optically functional parts include quantum-confined semiconductors, inorganic oxides, organic materials (small molecules), and polymers. The processable matrix materials are usually polymers but can also be copolymers, polymer blends, glass, or ceramics. 

Natural or synthetic HA has been intensively nsed in pure ceramic scaffolds as well as in polymer-ceramic composite systems. In fact, dne to calcinm phosphate osteocon-ductive properties, HA, TCP and BCP can be nsed as a scaffold matrix for bone-tissue engineering. However, these ceramic phases do not possess osteoinductive ability and their biodegradability is relatively slow, particularly in the case of crystalline HA (see Section 15.4.1). To overcome these drawbacks, biodegradable polymers added with osteogenic potential cells are used to make new biocomposite materials. Some of the tissue-engineered CP-polymer nanocomposite scaffolds are briefly described in the following sections, showing that both natural and synthetic polymers can be used to this aim. 

Polymer derived ceramic nanocomposites PDC-NCs are promising materials for structural and functional applications. They can be synthesized via polymer-to-ceramic conversion of suitable single-source precursors, leading in a first step to amorphous single-phase ceramics, which subsequently undergo phase separation processes to furnish bi- or multiphase ceramic nanocomposites (lonescu, 2012a). 

Polymer-derived ceramics and ceramic nanocomposites were extensively investigated in the last 15 years with respect to their (thermo)mechanical properties. Especially, their high-temperature creep behavior was shown to be outstanding, thus PDCs show near-zero steady state creep even at temperamres exceeding 1000 °C (Colombo, 2010a). This feature makes the PDCs quite unique with respect to other ceramic materials. 

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