scholarly journals Application of cesium hydroxide monohydrate for ring opening polymerization of monosubstituted oxiranes: characterization of synthesized polyether-diols

2020 ◽  
Author(s):  
Zbigniew Grobelny ◽  
Justyna Jurek-Suliga ◽  
Sylwia Golba
Keyword(s):  
Styrene Oxide ◽  
Glycidyl Ether ◽  
Complexing Agents ◽  
Glycidyl Ethers ◽  
Cesium Hydroxide ◽  
Allyl Glycidyl Ether ◽  
Main Fraction ◽  
Tetrahydrofuran Solution ◽  
Hydroxide Monohydrate

AbstractCesium hydroxide monohydrate (CsOH·H2O) activated by cation complexing agents, i.e., 18C6 or C222 was applied as initiator of monosubstituted oxiranes polymerization. Propylene oxide (PO), 1,2-butylene oxide (BO), styrene oxide (SO) and some glycidyl ethers were used as monomers. All processes were carried out in tetrahydrofuran solution at room temperature. Such polymers, as PPO-diols, PBO-diols and PSO-diols, are unimodal and have molar masses Mn = 2000–5100. Their dispersities are rather high (Mw/Mn = 1.17–1.33). Moreover, PPO-diols and PSO-diols are not contaminated by monools with unsaturated starting groups. Poly(glycidyl ether)s are, in general, polymodal. For example, poly(isopropyl glycidyl ether)-diols are bi- or trimodal, whereas poly(allyl glycidyl ether)-diols possess two or even six fractions. Molar masses of main fraction are 4200–6400, and the second fraction is much lower, namely 600–2600. Dispersities of some fractions are very low (Mw/Mn = 1.01–1.07). Polymodality of polymers obtained was discussed in terms of the formation of two or more species propagating with different rate constants. Graphic abstract

scholarly journals Application of Monopotassium Dipropylene Glycoxide for Homopolymerization and Copolymerization of Monosubstituted Oxiranes: Characterization of Synthesized Macrodiols by MALDI-TOF Mass Spectrometry

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2795
Author(s):  
Zbigniew Grobelny ◽  
Justyna Jurek-Suliga ◽  
Sylwia Golba
Keyword(s):  
Chemical Structure ◽  
Normal Pressure ◽  
Size Exclusion ◽  
Complexing Agent ◽  
Thermoplastic Polyurethanes ◽  
Maldi Tof ◽  
Glycidyl Ethers ◽  
Exclusion Chromatography ◽  
Tetrahydrofuran Solution

Monopotassium dipropylene glycoxide, activated by a 18-crown-6 cation complexing agent (K-DPG/L, where DPG (dipropylene glycol) is a mixture of isomers) was used as an effective initiator of the homopolymerization and copolymerization of several monosubstituted oxiranes, i.e., propylene oxide (PO), 1.2-butylene oxide (BO), and some glycidyl ethers such as allyl, isopropyl, phenyl, and benzyl ones (AGE, IPGE, PGE, and BGE, respectively). The copolymers are novel and can be prospectively used for the fabrication of new thermoplastic or crosslinked polyurethanes. All processes were carried out in homogeneous mild conditions, i.e., tetrahydrofuran solution at room temperature and normal pressure. They resulted in new unimodal macrodiols with Mn = Mcalc in the range of 1500–8300, low dispersity Mw/Mn = 1.08–1.18 and a chemical structure well defined by several techniques, i.e., MALDI-TOF, size exclusion chromatography (SEC), 13C NMR, and FTIR. Monopotassium salts of homopolyether-diols, i.e., PPO-diol, PBO-diol, and PAGE-diol, appeared to be useful macroinitiators for the preparation of new triblock copolyether-diols by polymerization of glycidyl ethers. In BO/BGE random copolymerization initiated with K-DPG/L, macromolecules of copolyether-diol were exclusively formed. Macromolecules of copolyether-diol accompanied by homopolyether PPO-diol were identified in the PO/PGE system. However, AGE and PGE reacted by giving random copolyether-diol as well as homopolymer-diols, i.e., PAGE-diol and PPGE-diol. Macromolecules of prepared copolyether-diols contain various numbers of mers deriving from comonomers; the kind of comonomer determines the composition of the product. Several prepared homopolyether-diols and copolyether-diols could be useful for the synthesis of new thermoplastic polyurethanes.

Preparation and Characterization of Temperature-Sensitive 2-Hydroxy-3-Allyloxy Propyl Starch Ether

2015 ◽  
Vol 752-753 ◽  
pp. 81-85
Author(s):  
Ben Zhi Ju ◽  
Wei Ma ◽  
Hong Liang Yuan ◽  
Shu Fen Zhang
Keyword(s):  
Aqueous Solution ◽  
Fluorescence Spectroscopy ◽  
Self Assembly ◽  
Glycidyl Ether ◽  
Degree Of Substitution ◽  
Temperature Sensitive ◽  
H Nmr ◽  
Hydrophilic Lipophilic Balance ◽  
Allyl Glycidyl Ether

A temperature-sensitive 2-hydroxy-3-allyloxy-propyl starch ehter (HAPS) was prepared by regulating the hydrophilic-lipophilic balance of etherified starch. Allyl glycidyl ether (AGE) was used as the hydrophobic reagent. 1H-NMR was used to characterize the structure of products and determine the degree of substitution of etherified starch. UV-Vis and fluorescence spectroscopy methods were adopted to investigate the properties of HAPS aqueous solution. The results showed that the LCST of HAPS was reduced as the DS. When the cmc of HAPS decreases and DS increases, formation of micelles in an aqueous solution by self-assembly is possible.

New amphiphilic copolymers derived from hydrophobically modified vinyl saccharides

1995 ◽  
Vol 73 (11) ◽  
pp. 1941-1947 ◽  
Author(s):  
Joachim Klein ◽  
Markwart Kunz ◽  
Lutz Guderjahn
Keyword(s):  
Aqueous Solution ◽  
Surface Tension ◽  
Glycidyl Ether ◽  
Vinyl Pyrrolidone ◽  
Hydrophobic Association ◽  
Amphiphilic Copolymers ◽  
Molecular Weights ◽  
Hydrophobically Modified ◽  
Allyl Glycidyl Ether

The synthesis and characterization of new amphiphilic copolymers derived from copolymerization of hydrophobically modified so-called vinyl saccharides with 1-vinyl-2-pyrrolidone are described. The vinyl saccharides were prepared in a two-step synthesis. In the first step hydrophobically modified saccharide derivatives were synthesized without protecting procedures by direct reductive amination of the reducing keto-disaccharide isomaltulose (Palatinose®) with n-dodecylamine. In the second step the resulting N-dodecylaminopolyols were coupled with allyl glycidyl ether to give polymerizable amphiphilic vinyl saccharides. The copolymerizations with 1-vinyl-2-pyrrolidone were performed as free radical aqueous solution polymerizations. The characterization of the copolymers was carried out by measuring the viscosity and light scattering in water as well as in trichloromethane, in addition to surface tension measurements and solubilization studies. The solution properties of the copolymers in water and trichloromethane differ remarkably. While the values for the intrinsic viscosities in both solvents are comparable, the weight-average molecular weights in water are much higher than those in trichloromethane, indicating the formation of aggregates in aqueous solution. The vinyl pyrrolidone copolymers are also very surface active, lowering the surface tension of water to as low as 30 mN/m. The combination of measurements of surface tensions and solubilization studies indicates that their hydrophobic association behaviour is formally comparable to those of low molecular weight surfactants. Keywords: vinyl saccharides, isomaltulose, hydrophobic association, amphiphilic polymers.

scholarly journals Allyl glycidyl ether-modified animal glue binder for improved water resistance and bonding strength in sand casting

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Chen-chen Fan ◽  
Qian Tang
Keyword(s):  
Tensile Strength ◽  
Bonding Strength ◽  
Room Temperature ◽  
Water Resistance ◽  
Glycidyl Ether ◽  
Animal Glue ◽  
Practical Application ◽  
Foundry Industry ◽  
Dog Bone ◽  
Allyl Glycidyl Ether

This paper aims to develop a modified animal glue sand binder for foundry casting with improved water resistance and bonding strength. An efficient method is reported by using sodium hydroxide as the catalyst to improve the operability of animal glue binder and allyl glycidyl ether as the modifier to improve the water resistance and bonding strength. Sand specimens prepared using allyl glycidyl ether-modified animal glue binder were cured by compressed air at room temperature. The proposed method saves energy and is environmentally friendly and inexpensive. Compared with unmodified animal glue binder, standard dog bone sand specimens with allyl glycidyl ether-modified animal glue binder had higher tensile strength of 2.58 MPa, flowability of 1.95 g, better water resistance (a lower decrease in tensile strength at 25 °C and relative humidity of 60%), and good collapsibility. This allyl glycidyl ether-modified animal glue binder is suitable for practical application in the foundry industry.

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