Search

The article titled "Topical section 'Advanced Testing of Soft Polymer Materials'" discusses the importance of using advanced testing methods to characterize and analyze soft polymer materials. The increasing demand for enhanced properties and capabilities in various industries, such as e-mobility, energy generation, information technology, soft robotics, and medical engineering, has led to the need for predictive and advanced laboratory testing. The article emphasizes the importance of accuracy, relevance, productivity, and cost-effectiveness in laboratory testing, as well as the development of new concepts for soft polymeric materials, including nanotechnology, self-healing, and eco-design. The scope of the article includes the development and application of advanced testing methods for chemical, rheological, mechanical, thermal, electrical, and magnetic analysis, as well as concepts for predictive testing and realistic load simulation. The article highlights the potential of simulation tools and artificial intelligence in predicting the behavior and durability of soft polymer materials. [Extracted from the article]

In this paper, a self-repairing polyurethane without external stimulation was synthesized. First, a reversible acyl hydrazone bond was introduced into the polyurethane molecular chain. The bond could be dynamically reversible under acidic stimulation to repair the material damage. After that, different contents of bis(2-ethylhexyl) phosphate components were added to modify the material in the synthesis, and its performance was compared to pure polyurethane (PU-0). The polymer was tested using digital viscometer, differential scanning calorimeter (DSC), thermogravimetric analysis (TG), tensile test, etc. The results showed that the addition of bis(2-ethylhexyl) phosphate can promote the healing of the material, so that the synthetic polyurethane material can be repaired to a certain extent without external stimulation. [ABSTRACT FROM AUTHOR]

Condensed tannins extracted from the Pinus radiata bark (PRTs) were used as a replacement for phenol in the synthesis of resol-type phenolic resins (FRs) and tested as polymer matrix in carbon nanofiber (CNF)-reinforced composite materials. The PRTs used herein contained a phenol and lignin content of 31 (Eq/L) and 35 (%w/w), respectively. The molecular weights of these polyphenols indicated the presence of 16 flavonoid units. Tannin resins were synthesized, and their characteristics were compared with those of the synthesized FRs using a formaldehyde/phenol ratio of (1.6/1.0), which has the highest total solids content. The results showed that the gel time and useful life of the resins decreased with the addition of the tannins, while there was no significant variation in the degradation temperature with varying FR contents. The mechanical properties of the CNF-reinforced composite materials were determined by DMA, and the results showed an increase of 1000 MPa, due to the better distribution of the fibers in the matrix. The modulus (E') in the reinforced composite materials with tannin resins was 2322 MPa and 1803 MPa without tannins, while modulus E¨ for composite materials doubled for resins with tannins. Tannins improved the dispersion of CNTs and the matrix-filled interface. [ABSTRACT FROM AUTHOR]

Sensitivity toward humidity, response and recovery time, and reproducibility behaviors of a novel copolymer sensor, obtained by oxidative chemical polymerization of o-phenylenediamine and aniline using D-camphor-10-sulfonic acid dopant, were reported. It is a novel copolymer, and there are very few studies available concerning its synthesis and humidity sensing applications. Humidity-sensitive properties of the copolymer were tested by measuring the resistance of the fabricated films, and good humidity sensitivity was obtained. Moreover, a decrease in resistance with the increase in humidity was observed. Compared to polyaniline (PANI), the humidity sensing property of the copolymer was found to show quicker response and recovery time, higher reproducibility, and higher sensitivity. However, PANI alone exhibited relatively poor sensing property. The response time for the copolymer films at the relative humidity ranging from 11 to 97% was about 38 s, and the corresponding recovery time was about 11 s. The value of sensitivity was about 10. These results indicate excellent sensing character of the new type of copolymer humidity sensors. The obtained sensor is expected to exhibit good humidity sensing behavior in moisture-containing environment. [ABSTRACT FROM AUTHOR]

A series of aromatic azothiazole and azobenzothiazole compounds containing vinyl have been designed as monomers. The polymers containing azothiazole and azobenzothiazole NLO chromophore in each side chain have been synthesized via free radical polymerization. The third-order NLO coefficient of monomers containing azothiazole and azobenzothiazole and their polymers were measured by Z-scan technique. The conjugation and push-pull electronic effect on the heteroatomic ring group contributes much to enhancing the NLO property. [ABSTRACT FROM AUTHOR]