Recent advances in superhydrophobic polyurethane: preparations and applications.

Even though polyurethane (PU) has been widely applied, its superhydrophobicity is inadequate for certain applications. As such, the development of superhydrophobic polyurethane (SHPU) has recently attracted significant attention, with numerous motivating reports in recent years. However, a comprehensive review that summarizes these state-of-the-art developments remains lacking. Thus, this review aims to fill up this gap by reviewing the recent preparation methods for SHPU based on superhydrophobic theories and principles. Three main types of methods used in promoting the hydrophobicity of PU are emphasized in this review; (1) incorporation of silicide or fluoride to lower the surface energy, (2) creation of micro/nano-scale rough surfaces by electrospinning or grafting of nanoparticles, and (3) integrating the earlier two methods to develop a synergistic approach. Furthermore, this review also discussed the various applications of SHPU in oil spill treatment, protective coating, self-healing materials and sensors.

Design of a Superhydrophobic Strain Sensor with a Multilayer Structure for Human Motion Monitoring.

A flexible strain sensor is of significant importance in wearable electronics since it can help monitor the physical signals from the human body. Among various strain sensors, the polyurethane (PU)-based ones have received widespread attention owing to their excellent toughness, large working range, and nice gas permeability. However, the hydrophobicity of these sensors is not good enough, which may affect their use life and sensitivity. In this work, a high-performance strain sensor composed of PU, reduced graphene oxide (rGO), polydopamine (PDA), and 1H,1H,2H,2H-perfluorodecane-thiol (PFDT) was designed and prepared. The results revealed that this PU/rGO/PDA/PFDT device possessed good superhydrophobicity with a water contact angle of 153.3°, a wide working strain range of 590%, and an outstanding gauge factor as high as 221 simultaneously. Because of these above advantages, the sensor worked effectively in detecting both subtle and large human movements (such as joint motion, finger motion, and vocal cord vibration) even in a high humidity environment. This strain sensor with high sensitivity, wide working range, and suitable modulus may have great potential in the field of flexible and wearable electronics in the near future.

Hepatocellular carcinoma with tumor thrombus in bile duct: A proposal of new classification according to resectability of primary lesion.

BACKGROUND: Hepatocellular carcinoma (HCC) with tumor thrombus in the bile duct (BDTT) is easily misdiagnosed or mistreated due to the clinicopathological diversity of the thrombus and its relationship with primary lesions. AIM: To propose a new classification for HCC with BDTT in order to guide its diagnosis and treatment. METHODS: A retrospective review of the diagnosis and treatment experience regarding seven typical HCC patients with BDTT between January 2010 and December 2019 was conducted. RESULTS: BDTT was preoperatively confirmed by computed tomography/magnetic resonance imaging in only four patients. Three patients with recurrent HCC and one patient with first-occurring HCC had no visible intrahepatic tumors; of these, misdiagnosis occurred in two patients, and three patients died. One patient was mistreated as having common bile duct stones, and another patient with a history of multiple recurrent HCC was misdiagnosed until obvious biliary dilation could be detected. Only one patient who received hepatectomy accompanied by BDTT extraction exhibited disease-free survival during the follow-up period. A new classification was proposed for HCC with BDTT as follows: HCC with microscopic BDTT (Type I); resectable primary or recurrent HCC mass in the liver with BDTT (Type II); BDTT without an obvious HCC mass in the liver (Type III) and BDTT accompanied with unresectable intra- or extrahepatic HCC lesions (Type IV). CONCLUSION: We herein propose a new classification system for HCC with BDTT to reflect its pathological characteristics and emphasize the significance of primary tumor resectability in its treatment.