A robust procedure for large scale synthesis of a high molar mass, unsubstituted poly(m,p-phenylene)

2015 ◽  
Vol 6 (45) ◽  
pp. 7833-7840 ◽  
Author(s):  
Bernd Deffner ◽  
A. Dieter Schlüter
Keyword(s):  
Large Scale ◽  
Molar Mass ◽  
Side Chains ◽  
High Molar Mass ◽  
Large Scale Synthesis

A high molar mass poly(m,p-phenylene) with acid cleavable side chains was synthesised. Further, the material was processed into films and subjected to a cleaving procedure yielding insoluble films of unsubstituted polyphenylene.

scholarly journals Epidermal biopolysaccharides from plant seeds enable biodegradable turbulent drag reduction

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Anoop Rajappan ◽  
Gareth H. McKinley
Keyword(s):  
Turbulent Flow ◽  
Drag Reduction ◽  
Large Scale ◽  
Molar Mass ◽  
Raw Material ◽  
Large Reynolds Number ◽  
Frictional Drag ◽  
High Molar Mass ◽  
Plant Seeds ◽  
Cost Constraints

AbstractThe high cost of synthetic polymers has been a key impediment limiting the widespread adoption of polymer drag reduction techniques in large-scale engineering applications, such as marine drag reduction. To address consumable cost constraints, we investigate the use of high molar mass biopolysaccharides, present in the mucilaginous epidermis of plant seeds, as inexpensive drag reducers in large Reynolds number turbulent flows. Specifically, we study the aqueous mucilage extracted from flax seeds (Linum usitatissimum) and compare its drag reduction efficacy to that of poly(ethylene oxide) or PEO, a common synthetic polymer widely used as a drag reducing agent in aqueous flows. Macromolecular and rheological characterisation confirm the presence of high molar mass (≥2 MDa) polysaccharides in the extracted mucilage, with an acidic fraction comprising negatively charged chains. Frictional drag measurements, performed inside a bespoke Taylor-Couette apparatus, show that the as-extracted mucilage has comparable drag reduction performance under turbulent flow conditions as aqueous PEO solutions, while concurrently offering advantages in terms of raw material cost, availability, and bio-compatibility. Our results indicate that plant-sourced mucilage can potentially serve as a cost-effective and eco-friendly substitute for synthetic drag reducing polymers in large scale turbulent flow applications.

Exogenous Directing Group Free, Ligand-Enabled gamma-C(sp3)–H Arylation of Free Primary Aliphatic Amines and α-Amino Esters

2019 ◽  
Author(s):  
Yongzheng Ding ◽  
Shuai Fan ◽  
Xiaoxi Chen ◽  
yuzhen gao ◽  
Gang Li
Keyword(s):  
Amino Acids ◽  
Large Scale ◽  
Free Ligand ◽  
Aliphatic Amines ◽  
Rapid Synthesis ◽  
Amino Esters ◽  
Directing Group ◽  
Large Scale Synthesis ◽  
Primary Aliphatic Amines

A Pdᴵᴵ-catalyzed, ligand-enabled gamma-C(sp3)–H arylation of free primary aliphatic amines and amino esters without using an exogenous directing group is reported. This reaction is compatible with unhindered free aliphatic amines, and it is also be applicable to the rapid synthesis of biologically and synthetically valuable unnatural α-amino acids. Large scale synthesis is also feasible using this method.<br>

A Simplified Protocol for the ortho-Deuteration of Acidic Aromatic Compounds in D2O

2019 ◽  
Author(s):  
Alyssa Garreau ◽  
Hanyang Zhou ◽  
Michael Young
Keyword(s):  
Carboxylic Acid ◽  
Aromatic Compounds ◽  
Large Scale ◽  
Simplified Approach ◽  
Directing Group ◽  
Large Scale Synthesis

<div>Methods to catalytically introduce deuterium in synthetically useful yields ortho to a carboxylic acid directing group on arenes typically requires D2 or CD3CO2D, which makes using these approaches cost prohibitive for large scale synthesis (equipment and reagent costs respectively). Herein we present a simplified approach using catalytic RhIII and D2O as deuterium source, and show its application to H/D exchange on various acidic substrates.</div>

A Simplified Protocol for the ortho-Deuteration of Acidic Aromatic Compounds in D2O

2019 ◽  
Author(s):  
Alyssa Garreau ◽  
Hanyang Zhou ◽  
Michael Young
Keyword(s):  
Carboxylic Acid ◽  
Aromatic Compounds ◽  
Large Scale ◽  
Simplified Approach ◽  
Directing Group ◽  
Large Scale Synthesis

<div>Methods to catalytically introduce deuterium in synthetically useful yields ortho to a carboxylic acid directing group on arenes typically requires D2 or CD3CO2D, which makes using these approaches cost prohibitive for large scale synthesis (equipment and reagent costs respectively). Herein we present a simplified approach using catalytic RhIII and D2O as deuterium source, and show its application to H/D exchange on various acidic substrates.</div>

Paper Chemistry: Interactions of thermo mechanical pulp fractions with high molar mass cationic polyacrylamides: Part 2. Flocculation

2010 ◽  
Vol 25 (3) ◽  
pp. 310-318 ◽  
Author(s):  
Tero Taipale ◽  
Janne Laine ◽  
Susanna Holappa ◽  
Jonni Ahlgren ◽  
Juan Cecchini
Keyword(s):  
Molar Mass ◽  
High Molar Mass ◽  
Mechanical Pulp ◽  
Paper Chemistry

Improved and Large-Scale Synthesis of N-methyl-D-aspartic Acid

2015 ◽  
Vol 12 (2) ◽  
pp. 197-201 ◽  
Author(s):  
Liang Xi ◽  
Di Wu ◽  
Hong-You Zhu ◽  
Cong-Hai Zhang ◽  
Yi Jin ◽  
...  
Keyword(s):  
Aspartic Acid ◽  
Large Scale ◽  
Large Scale Synthesis

Large-scale synthesis of copper nanoparticles by chemically controlled reduction for applications of inkjet-printed electronics

2008 ◽  
Vol 19 (41) ◽  
pp. 415604 ◽  
Author(s):  
Youngil Lee ◽  
Jun-rak Choi ◽  
Kwi Jong Lee ◽  
Nathan E Stott ◽  
Donghoon Kim
Keyword(s):  
Copper Nanoparticles ◽  
Large Scale ◽  
Printed Electronics ◽  
Large Scale Synthesis

scholarly journals Highly Efficient MOF Catalyst Systems for CO2 Conversion to Bis-Cyclic Carbonates as Building Blocks for NIPHUs (Non-Isocyanate Polyhydroxyurethanes) Synthesis

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 628
Author(s):  
Adolfo Benedito ◽  
Eider Acarreta ◽  
Enrique Giménez
Keyword(s):  
Molar Mass ◽  
Cycloaddition Reaction ◽  
Building Blocks ◽  
Catalyst System ◽  
Cyclic Carbonate ◽  
Ammonium Bromide ◽  
Cyclic Carbonates ◽  
High Molar Mass ◽  
Highly Efficient ◽  
Free Process

The present paper describes a greener sustainable route toward the synthesis of NIPHUs. We report a highly efficient solvent-free process to produce [4,4′-bi(1,3-dioxolane)]-2,2′-dione (BDC), involving CO2, as renewable feedstock, and bis-epoxide (1,3-butadiendiepoxide) using only metal–organic frameworks (MOFs) as catalysts and cetyltrimethyl-ammonium bromide (CTAB) as a co-catalyst. This synthetic procedure is evaluated in the context of reducing global emissions of waste CO2 and converting CO2 into useful chemical feedstocks. The reaction was carried out in a pressurized reactor at pressures of 30 bars and controlled temperatures of around 120–130 °C. This study examines how reaction parameters such as catalyst used, temperature, or reaction time can influence the molar mass, yield, or reactivity of BDC. High BDC reactivity is essential for producing high molar mass linear non-isocyanate polyhydroxyurethane (NIPHU) via melt-phase polyaddition with aliphatic diamines. The optimized Al-OH-fumarate catalyst system described in this paper exhibited a 78% GC-MS conversion for the desired cyclic carbonates, in the absence of a solvent and a 50 wt % chemically fixed CO2. The cycloaddition reaction could also be carried out in the absence of CTAB, although lower cyclic carbonate yields were observed.

Large-scale synthesis of ionic liquid [BMIM]Br in a microbore tube

2021 ◽  
Author(s):  
Nirvik Sen ◽  
Sameer Ekhande ◽  
K.K. Singh ◽  
S. Mukhopadhyay ◽  
R.S. Sirsam ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Large Scale ◽  
Large Scale Synthesis
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