scholarly journals Tacky-Free Polyurethanes Pressure-Sensitive Adhesives by Molecular-Weight and HDI Trimer Design

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2164
Author(s):  
Ji-Hong Bae ◽  
Jong-Chan Won ◽  
Won-Bin Lim ◽  
Byeong-Joo Kim ◽  
Ju-Hong Lee ◽  
...  

Polyurethane pressure-sensitive adhesives (PU-PSAs) with satisfactory tack, cohesion, and removability were newly developed through the synthetic process by reacting methylene diisocyanate, poly(ethylene glycol) (PEG), and a 1,4-butanediol chain extender based on the different HDI/HDI trimer ratios. The sticking properties of PU-PSAs depended on both the HDI/HDI trimer ratio and crosslinking-agent composition in the formulation. The molecular weight (MW) dependence of adhesion in PU-PSA was observed in the range of 1000 < Mn < 3000, suggesting that the increase in MW limits the pressure-sensitive adhesion of these samples. The differences in the crosslinking-density significantly affected the cohesion, adhesion, and tack in PU-PSA. The formulation of 50 wt.% 600PEG and 50 wt.% crosslinking-agent and an HDI/HDI trimer ratio of 1.0 led to the optimal balance between the adhesion and cohesion properties owing to the sufficient tack, high 180-peel strength, and good cohesion.

2014 ◽  
Vol 47 (16) ◽  
pp. 5759-5767 ◽  
Author(s):  
Mikhail M. Feldstein ◽  
Kermen A. Bovaldinova ◽  
Eugenia V. Bermesheva ◽  
Alexander P. Moscalets ◽  
Elena E. Dormidontova ◽  
...  

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 648
Author(s):  
Xiangning Wen ◽  
Yunlan Su ◽  
Shaofan Li ◽  
Weilong Ju ◽  
Dujin Wang

In this work, the crystallization kinetics of poly(ethylene oxide) (PEO) matrix included with poly(ethylene glycol) (PEG) grafted silica (PEG-g-SiO2) nanoparticles and bare SiO2 were systematically investigated by differential scanning calorimetry (DSC) and polarized light optical microscopy (PLOM) method. PEG-g-SiO2 can significantly increase the crystallinity and crystallization temperature of PEO matrix under the non-isothermal crystallization process. Pronounced effects of PEG-g-SiO2 on the crystalline morphology and crystallization rate of PEO were further characterized by employing spherulitic morphological observation and isothermal crystallization kinetics analysis. In contrast to the bare SiO2, PEG-g-SiO2 can be well dispersed in PEO matrix at low P/N (P: Molecular weight of matrix chains, N: Molecular weight of grafted chains), which is a key factor to enhance the primary nucleation rate. In particular, we found that the addition of PEG-g-SiO2 slows the spherulitic growth fronts compared to the neat PEO. It is speculated that the interfacial structure of the grafted PEG plays a key role in the formation of nuclei sites, thus ultimately determines the crystallization behavior of PEO PNCs and enhances the overall crystallization rate of the PEO nanocomposites.


2007 ◽  
Vol 208 (24) ◽  
pp. 2642-2653 ◽  
Author(s):  
Alena Braunová ◽  
Michal Pechar ◽  
Richard Laga ◽  
Karel Ulbrich

2012 ◽  
Vol 567 ◽  
pp. 123-126
Author(s):  
Teng Fei Shen ◽  
Man Geng Lu ◽  
Li Yan Liang

In this work, microporous membrane biomaterials based on high weight molecular polylactide (PLA) and low molecular weight poly(ethylene glycol) (PEG) using rapid solvent evaporation method were prepared and investigated. The effect of PEG segments added on the thermal and degradation behaviors was studied. According to the results, produced PLA/PEG biomaterial has lower glass transition temperature (Tg)in comparison with neat PLA. It was also found that the degradation rates of the PLA/PEG biomaterials were significantly increased with adding of PEG, which explained by increasing hydrophilic groups. For better porous fixation, CL-blocked polyisocyanate (CL-bp), which was synthesized from reaction of isophorone diisocyanate (IPDI) with dimethylol propionic acid (DMPA) and Trimethylolpropane (TMP) followed by addition of caprolactam (CL), were introduced. The microporous forms were observed by the scanning electron microscope (SEM), which showed the mean diameters of prepared PLA/PEG microporous were around 10μm.


Sign in / Sign up

Export Citation Format

Share Document