Elastomeric polymers, transparent

The hard segments content was 30 wt. % by feed in all materials - resulting in soft, transparent and elastomeric polymers, only the nanofiller amount varied as 0.1, 0.2 and 0.3 wt. %, respectively. The segmental composition and the nanofiller amount were selected upon previous experience with Ti02-based polymer matrix nanocomposites [4]. 

If the hydrolyses in silane precursor-polymer systems are carried out using relatively large amounts of the silane, then the silica generated can become the continuous phase, with the elastomeric polysiloxane dispersed in it.12 14 136-143 Again, a variety of ceramic components and polymeric components have been studied. The resultant composite is a polymer-modified glass or ceramic, frequently of very good transparency. Although its thermal stability will be inferior to that of the ceramic component itself, there are many applications for ceramic-type materials where this is not a serious problem. 

The semicrystalline PCL and branched amorphous PCL were also combined in a block copolymer structure giving transparent elastomeric films. The block copolymers were made by RROP of MDO or copolymerization of MDO with MMA using a semicrystalline PCL azo initiator. The polymers were degradable, transparent, and elastic, depending upon the copolymer composition and block length (Figure 2.7) [69]. 

Styrene-butadiene block copolymers (SBC) with a high (70-85 %) styrene content are commercially produced and marketed as transparent, stiff, and tough thermoplastic resins under the trade names of Styrolux (Styrolution), K-Resin (Chevron-Phillips), Finaclear (Total petrochemical), and Clearene (Denka-Kaguku). Unlike other more elastomeric types of styrene-butadiene block copolymers, the rigid SBC resins contain only <25 % polybutadiene rubber content. Structurally, these SBC polymers are composed of polystyrene (S) and polybutadiene (B) blocks, linked together in an unsymmetrical star-block [(S-B)x] structure. 

Acrylate polymers are often used in many applications that require good optical properties. However, they are unsuitable for use in the automotive industry because of their brittle characteristics. Thus, when natural rubber is blended with poly(methyl methacrylate), there is a big improvement in the elasticity of the brittle acrylate polymers. It is of interest that thermoplastic natural rubbers are relatively new products in the rubber industry and are fastgrowing items in the polymer market. The acrylate polymers blended with natural rubber can improve various properties of both the natural rubber and the acrylate polymers such as elasticity, adhesion, processability properties, and transparency. These materials are known for their excellent processability, characteristic of acrylate polymers, and their elasticity property provided by natural rubber, thus they exhibit the typical properties of elastomeric materials and can be processed with thermoplastic processing equipment used to prepare acrylate polymers. Many of their interesting properties have been widely developed for several industrial applications such as in the automotive industry, household appliances, medical devices, electrical cables, and headphone cables. ... 

When no high accuracy alignment is needed and low pressure is used in UV-NIL, the mechanical properties of the mold can be relaxed. Then, mold copies can also be obtained by replicating elastomeric materials like Poly(dimethylsiloxane) (PDMS), which is a soft UV-transparent material in the 340-600 nm wavelength region [111, 112]. Finally, the ultimate stamp copy process was presented by Obducat with the Intermediate Polymer Stamp [113]. Here, the polymer stamp is used only once, avoiding any mold contamination or erosion issues. 

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