scholarly journals Rheology and Physical Properties of Polysulfone in-situ Reinforced with a Thermotropic Liquid-Crystalline Polyester

1991 ◽  
Vol 23 (11) ◽  
pp. 1347-1357 ◽  
Author(s):  
Soon Man Hong ◽  
Byoung Chul Kim ◽  
Kwang Ung Kim ◽  
In Jae Chung
Keyword(s):  
Physical Properties ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polyester

Improving Stiffness, Strength, and Toughness of Poly(ω-pentadecalactone) Fibers through in Situ Reinforcement with a Vanillic Acid-Based Thermotropic Liquid Crystalline Polyester

2016 ◽  
Vol 49 (6) ◽  
pp. 2228-2237 ◽  
Author(s):  
Carolus H. R. M. Wilsens ◽  
Mark P. F. Pepels ◽  
Anne B. Spoelstra ◽  
Giuseppe Portale ◽  
Dietmar Auhl ◽  
...  
Keyword(s):  
Vanillic Acid ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polyester ◽  
Strength And Toughness

scholarly journals Microstructural Characteristics of Frazil Particles and the Physical Properties of Frazil Ice in the Yellow River, China

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 617
Author(s):  
Yaodan Zhang ◽  
Zhijun Li ◽  
Yuanren Xiu ◽  
Chunjiang Li ◽  
Baosen Zhang ◽  
...  
Keyword(s):  
Physical Properties ◽  
Yellow River ◽  
The Yellow River ◽  
Ice Crystal ◽  
Microstructural Characteristics ◽  
Air Bubble ◽  
Frazil Ice ◽  
Sediment Content ◽  
Crystal Diameter

Frazil particles, ice crystals or slushy granules that form in turbulent water, change the freezing properties of ice to create “frazil ice”. To understand the microstructural characteristics of these particles and the physical properties of frazil ice in greater depth, an in situ sampler was designed to collect frazil particles in the Yellow River. The ice crystal microstructural characteristics of the frazil particles (morphology, size, air bubble, and sediment) were observed under a microscope, and their nucleation mechanism was analyzed according to its microstructure. The physical properties of frazil ice (ice crystal microstructure, air bubble, ice density, and sediment content) were also observed. The results showed that these microstructures of frazil particles can be divided into four types: granular, dendritic, needle-like, and serrated. The size of the measured frazil particles ranged from 0.1 to 25 mm. Compared with columnar ice, the crystal microstructure of frazil ice is irregular, with a mean crystal diameter less than 5 mm extending in all directions. The crystal grain size and ice density of frazil ice are smaller than columnar ice, but the bubble and sediment content are larger.

Synthesis and Properties of Biodegradable Liquid Crystalline Poly(ester-Urethane)s Based on Poly(L-Lactic Acid)

2013 ◽  
Vol 652-654 ◽  
pp. 459-462
Author(s):  
Ya Tong Guo ◽  
Zhu Zheng ◽  
Zhen Qi Hou ◽  
Jie Du
Keyword(s):  
Phase Transition ◽  
Thermal Stability ◽  
Lactic Acid ◽  
Physical Properties ◽  
Liquid Crystalline ◽  
Degradation Rate ◽  
Hydrolytic Degradation ◽  
Hexamethylene Diisocyanate ◽  
Solution Polymerization ◽  
Phase Transition Temperatures

A series of biodegradable segmented liquid crystalline poly(ester-urethane)s were prepared by solution polymerization of poly(L-lactic acid) (PLLA), mesogenic diol prepolymer poly(butylene terephthaloyldioxy dibenzoates) (MD), and hexamethylene diisocyanate (HDI). The MD content was varied from 0 to 40 mol% so that the effects of the mesogen content on the thermal and physical properties, and hydrolytic degradation were examined respectively. It was found that introducing mesogens units could increase the thermal stability and the elastic properties, while reduced the phase transition temperatures and the hydrolytic degradation rate.

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