Triethoxysilyl modified styrene-butadiene rubber latex was synthesized by the emulsion copolymerization of 2-(3-triethoxysilylpropyl)-1, 3-butadiene with styrene and 1, 3-butadiene. This latex was mixed with unmodified SBR latex and tetraethoxysilane to obtain SBR-silica composites by sol-gel reaction in the latex. Evaluation of mechanical properties demonstrated that tensile modulus and tensile strength, elongation at break improved with increasing of the amount of modified SBR. SEM observation for SBR-silica composites suggested that particle size of silica dispersed in unvulcanized rubber matrix grew larger with decreasing of silica content.

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Melting of nanosize crystals of ice and polymer measured with differential scanning calorimeter (DSC) has been reviewed on the research work by the present authors. The whole article was divided into the two parts due to limitations of space. In part 1, melting of nanosize ice has been treated.
Firstly the thermodynamic aspect of melting point depression of nanosize crystals was treated briefly. The inversely proportional increase of specific surface area due to the decrease of crystal size was explained to be the origin of the melting point lowering from the equilibrium value.
Secondly the melting point of ice formed in water-saturated microporous materials such as silica gels for HPLC use and polymer hydrogel membranes for artificial kidneys revealed the depression from 0°C inherent to its crystal size. This encouraged us to establish a new technique called “Thermoporosimetry” which can measure the pore size distribution (PSD) curve of porous materials thermally. The most advantage of this technique is that it can measure the PSD curve of polymer hydrogel for which the already existing techniques such as gas adsorption method and mercuryporosimetry cannot apply because the prior freeze-drying of the hydrogel samples destroys their nanosize pores.

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It has been pointed out that polymer crystals which are of nanosize by nature do not show the melting point lowering inherent to their size as the ice in nanopore surely did as described in Part 1, because of the inevitable reorganization of the original crystal to larger size during DSC-heating. γ-ray irradiating of nylon 6 and 66 in gaseous acetylene provided an effective technique to prevent such reorganization. Thus obtained DSC curve of the sample gave the true melting point of the original crystal.
It has been clarified quantitatively that the double melting peaks of nylon 6 are the result of superposition of three processes which occur successively during heating: perfection of the original crystal, melting of the perfected crystal concurrently with recrystallization, and final melting of the recrystallized crystal.

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Pressure sensitive adhesive (PSA) tapes are used in various applications such as electrical insulation, surface protection, nameplate adhesives, medical care, and household uses. Double-coated PSA tapes are used for the same usage as the adhesive. However, the bulky physical properties of PSA tapes are ruled by the factors of their own properties, though interfacial properties are ruled by the factors of the adhesive.
I will explain some technical characteristics about PSA tapes in serial 6 chapters. This is the 1st chapter and explained about out-lines of PSA tape's usage and some examples of material designs for them.

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