Synthesis and storage stability investigation on curing agent microcapsules of imidazole derivatives with aqueous polyurethane as the shell

2022 ◽  
Author(s):  
Yi-fei Zhang ◽  
Jian-zhong Liu ◽  
Jian Li ◽  
Chen-yi Wang ◽  
Qiang Ren
Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1397
Author(s):  
Nappaphan Kunanusont ◽  
Boonchai Sangpetngam ◽  
Anongnat Somwangthanaroj

Plastic waste has been incorporated with asphalt to improve the physical properties of asphalt and alleviate the increasing trend of plastic waste being introduced into the environment. However, plastic waste comes in different types such as thermoplastic or thermoset, which results in varied properties of polymer modified asphalt (PMA). In this work, four thermoplastic vulcanizates (TPVs) were prepared using different peroxide concentrations to produce four formulations of gel content (with varying extent of crosslinked part) in order to imitate the variation of plastic waste. All four TPVs were then mixed with asphalt at 5 wt% thus producing four formulations of PMA, which went through physical, rheological, and storage stability assessments. PMA with higher gel content possessed lower penetration and higher softening temperature, indicating physically harder appearance of PMA. Superpave parameters remained unchanged among different gel content PMA at temperatures of 64, 70, and 76 °C. PMA with any level of gel content had lower Brookfield viscosity than PMA without gel content at a temperature of 135 °C. Higher gel content resulted in shorter storage stability measured with greater different softening temperatures between top and bottom layers of PMA after 5 days of 163 °C storage. This study shows that asphalt with thermoset plastic waste is harder and easier to pave, thus making the non-recycling thermoset plastic waste more useful and friendly to the environment.


Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 47
Author(s):  
Julius Rami ◽  
Caroline Dumler ◽  
Nadine Weber ◽  
Michael Rychlik ◽  
Gabriele Netzel ◽  
...  

Folate (Vitamin B9) is critical for a range of biological functions in adults and children, including DNA, protein and neurotransmitter synthesis. It is also essential for the healthy development of the fetus in early pregnancy and for the prevention of neural tube defects, such as spina bifida. Strawberries are considered a tasty and healthy fruit consumed all over the world and may potentially be an important dietary source of natural folates. However, the relative importance of strawberry as a dietary source will depend on the total folate concentration, vitamer profile, storage stability and bioavailability to humans. Red Rhapsody, an important commercial strawberry cultivar in Australia, was screened for its folate content and storage stability by stable isotope dilution assay (SIDA). Total folate content ranged from 90–118 μg/100 g fresh weight (fw), which was well above the value in the Australian Food Composition Database (39 μg/100 g fw). 5-Methyltetrahydrofolate, the biologically active form in humans, was the principal vitamer present. Furthermore, folate remained relatively stable during refrigerated (4 °C) storage (loss of only 28% after 14 days of storage). This information is relevant for consumers since the inherent perishability of strawberry fruit makes refrigerated storage common practice in Australian households.


Author(s):  
Cindy T. Sepúlveda ◽  
Ailén Alemán ◽  
José E. Zapata ◽  
M. Pilar Montero ◽  
M. Carmen Gómez-Guillén

LWT ◽  
2021 ◽  
pp. 111463
Author(s):  
Tingting Hong ◽  
Qiyan Zhao ◽  
Dan Xu ◽  
Yirong Yuan ◽  
Yue Ma ◽  
...  

2021 ◽  
Vol 350 ◽  
pp. 129249
Author(s):  
Qais Ali Al-Maqtari ◽  
Abduljalil D.S. Ghaleb ◽  
Amer Ali Mahdi ◽  
Waleed Al-Ansi ◽  
Abeer Essam Noman ◽  
...  

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 722
Author(s):  
Shuji Yomo

In this study, a 2-pack isocyanate curing waterborne paint (without organic solvents) encapsulating dibutyltin dilaurate (hereinafter, DBTL) in nonionic surfactant micelles with an hydrophilic–lipophilic balance of 13–14 in advance releases DBTL when the micelles are collapsed at 80 °C or higher, whereby the curing progresses rapidly. On the other hand, the viscosity levels of the paint before and after being left at 40 °C for 1 h are almost the same. Organic solvents are mandatory for waterborne paints to provide paint and film properties, but they might collapse the micelles when they are formulated in the paint. In this study, we investigate whether the abovementioned paint containing organic solvents can develop switching functionality in terms of maintaining the storage stability at 40 °C and expressing a catalytic function at 80 °C to progress the curing. As a result, we find that if the solubility of the organic solvent in water at 20 °C is at least 10 g/100 mL and the boiling point is ≤200 °C, both curing and storage stability can be achieved.


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