The physical properties and structure of the interface between polyacrylates and metals were studied using scanning differential calorimetry，dielectric measurements，transmitting electron microscopy，X-ray diffractometry，and rheological measurements．Thin films of polyacrylates contacting with silver，and the composite of polyacrylates and metallic alloy with low melting temperature were prepared in order to investigate the interaction from metal to polyacrylates，and from polyacrylates to metals，respectively．The measurements for the films of polyacrylates contacting with silver indicated the existence of the interfacial phase in polyacrylates with lower molecular mobility and higher glass transition temperature．The results of the experiments for the composite of polyacrylates and metallic alloy showed the formation of nano-sized metallic particles with melting temperature lower than that of the same metallic alloy in the bulk phase．The suppression of the crystallization of the metals was also observed in the composites．The relation between the good adhesive properties of polyacrylates to metals，and the interfacial interaction between polyacrylates and metals was discussed based on the experimental results．

View full abstract

The probe tack，the dynamic mechanical analysis (DMA)，and the pulsed NMR of a silicone PSAs were measured. The elucidation of the behavior of a tack was tried from the relaxation spectrum and the dynamic mechanical analysis. From the analysis of the relaxation spectrum，it becomes clear that the value of a probe tack depend in a large part on the quantity of MQ resin that exists in a hard segment. DMA was measured in order to divide the behavior of this MQ resin into a contact process and a debonding process. In the contact process，the temperature at which E' was 10⁵Pa was converted into the temperature of probe tack measurement by using the WLF equation.Moreover，in a debonding process，probe tack measurement temperature is equivalent to a temperature low 80℃ in DMA measurement. Therefore，E'　 is decreasing monotonously with 　a rise in temperature. Thatis，in a debondingprocess，the value of a tack becomes large at low temperature. From a contact process and a debonding process，a probe tack will indicate the maximum value with the reduced temperature at which E' is10⁵Pa. This result isconforming to the evaluated result of a probe tack.

View full abstract

Composite adhesives composed of emulsion-based acrylic pressure sensitive adhesives (Em-PSA) and a small amount of single-walled carbon nanotubes (SWCNT) were prepared in water system by the assistance oftwo dispersants，carboxymethyl cellulose sodium salt and rutin. Optical microscopic observation revealed that the dispersants markedly improved the dispersion of SWCNT. Transmission electron microscope and electrical resistance measurement indicated that SWCNT were located at the interface between emulsion particles and constructed the conductive network in the Em-PSA composites at 0.43phr or more of SWCNT loading to the polymer solid content. SWCNT also reinforced the weak interfacial regions between emulsion particles，and resultantly peel creep resistance and shear strength of the composites were improved at high temperature.

View full abstract

Nanoimprint technologies have been received considerable attention due to their attractive features such as capabilities of the rapid fabrication and large scale patterning of nano/microstructures using patterned master substrates. In this paper，we report pressure sensitive adhesives designed for a UV-type nanoimprint process (PSA-NIP) ，in which the pressure sensitive adhesive sheet is applied to a patterned master stamp in order to transfer its pattern to the surface of the sheet，and then the sheet is photocured by irradiating ultraviolet light to maintain the transferred pattern and peel the cured sheet from the stamp. In dynamic rheological analyses and evaluating resolution of transferred patterns by using atomic force microscope (AFM) ，the adhesives composed of acrylic copolymers having vinyl groups and the photocurable resin havingrelatively high glass transition temperature (Tg，ca. 187℃) ，tricyclodecandiacrylate (TCDDA) ，show significant improvements in feature fidelity and thermal resistance.

View full abstract