Physical Properties of Amines

3 Key excerpts on "Physical Properties of Amines"

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  eBook - ePub

  Ullmann's Fine Chemicals

  • (Author)
  • 2014(Publication Date)
  • Wiley-VCH

    (Publisher)

  N -alkyl-1,3-propanediamines. Of commercial importance are fatty amine mixtures, such as coco amine, tallow amine, hydrogenated tallow amine, oleylamine, and soya amine, which are derived from naturally occurring fatty acids. More recently, alkylamines of similar structure were produced from synthetic feedstocks such as olefins or paraffins, and these also are called fatty amines (β-amines, branched chain amines, aminoalkanols). Only partly covered are fatty amine ethoxylates, fatty alkyl quaternary ammonium salts, alkyl betaines and fatty amine oxides, although all of these are fatty amine derivatives.

  7.1. Properties

  Physical Properties. Table 2 lists typical compositions of fatty amine mixtures. The properties of these can be varied to some extent by blending chain lengths with the desired physical characteristics. Fatty acids are also available in fractionated form and thus narrower ranges of fatty amines may be produced.

  Table 2 Mixture composition of primary fatty amines (mass fraction in %) [157]

  Solubilities of selected fatty amines in polar and nonpolar organic solvents are given in Table 3 . Only the short-chain fatty amines with 8 – 10 °C atoms per alkyl chain are of limited solubility in water.

  Table 3 Solubility (g per 100 mL at 30 °C) of fatty amines in organic solvents [158]

  2-Propanol	Hexane
  Primary amines
  Dodecylamine	∞	∞
  Tetradecylamine	458	216
  Hexadecylamine	169	64.8
  Octadecylamine	86	27.9
  Secondary amines
  Dioctylamine	∞	∞
  Didodecylamine	55	27.5
  Dioctadecylamine	1.2 (50 °C)	2.1 (40 °C)
  Tertiary amines
  Trioctylamine	∞	∞
  Tridodecylamine	23.9	∞
  Trioctadecylamine		36.4

  Vapor Pressures at ambient temperature are generally very low and decrease from 26.5 Pa for dodecylamine to 2.7 × 10−2 Pa (0.27 × 10−3 mbar) for eicosylamine. Some physical properties of pure compounds and commercial mixtures are given in Table 4 .

  Table 4 Physical properties of fatty amines [159–162]

  The oscillation of melting points between the series of odd-chain and even-chain homologues is shown in Figure 2 . This effect disappears in derivatives of primary fatty amines.

  Figure 2. Melting points of primary amines

  Almost all amines derived from natural sources have an even number of carbon atoms. Diamines and 2-(alkylimino)diethanols [N ,N

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  eBook - ePub

  Chemistry and Chemical Engineering for Sustainable Development

  Best Practices and Research Directions

  • Miguel A. Esteso, Ana Cristina Faria Ribeiro, A. K. Haghi, Miguel A. Esteso, Ana Cristina Faria Ribeiro, A. K. Haghi(Authors)
  • 2020(Publication Date)
  • Apple Academic Press

    (Publisher)

  CHAPTER 4

  THERMODYNAMIC AND TRANSPORT PROPERTIES OF AMINO ACIDS IN AQUEOUS SOLUTION

  CARMEN M. ROMERO

  1 *

  and MIGUEL A. ESTESO2

  1 Universidad Nacional de Colombia, Bogotá, Colombia

  2 Universidad de Alcalá, Alcalá de Henares, Spain * Corresponding author. E-mail: [email protected]

  ABSTRACT

  Amino acids can be considered as mixed solutes that contain hydrophilic groups (amine and carboxyl) and the hydrophobic aliphatic chain. These facts, combined with their biological importance, make the study of the physicochemical properties of these compounds in aqueous solvents very interesting and relevant. The information about structural changes derived from their physicochemical properties contributes to the interpretation of solute-solvent and solute-solute interactions in aqueous solutions.

  The amino acids considered in this work are α-amino acids and, α,ω-amino acids. They are: glycine, DL-α-alanine (2-aminopropanoic acid), DL-α-aminobutyric acid (2-aminobutanoic acid), DL-α-norvaline (2-aminopentanoic acid), DL-α-norleucine (2-aminohexanoic acid), β-alanine (3-aminopropanoic acid), γ-aminobutyric acid (4-aminobutanoic acid), 5-aminovaleric acid (5-aminopentanoic acid), and 6-aminocaproic acid (6-aminohexanoic acid).

  The compounds selected have a linear hydrocarbon chain that increases its length by one methylene group allowing the application of additivity approaches to the properties at infinite dilution of these systems.

  4.1 INTRODUCTION

  Amino acids are organic compounds that contain a basic (-NH2 ) and an acid carboxyl (-COOH) functional groups, along with a generic side chain (R group) characteristic of each amino acid; they can contain other functional groups.

  Several classifications of amino acids have been proposed according to their characteristics such as polarity, side chain group, hydrophobicity and the locations of the principal functional groups as alpha- (α-), beta- (β-), gamma- (γ-) or delta- (δ-) amino acids. When amino acids have the amine group bound to the first (alpha-) carbon atom adjacent to the carboxylic group, they are called 2-, or α-amino acids. When the amine group is attached to the other terminal carbon atom, called the omega (ω) carbon atom, they are named α,ω-amino acids. The alpha carbon is a chiral carbon atom. The alpha-amino acids are the most common form found in nature, but only in the L-isomer with the exception of glycine that does not has a chiral carbon atom.

  1 –3

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  eBook - ePub

  Basic Concepts of Environmental Chemistry

  • Des W. Connell(Author)
  • 2005(Publication Date)
  • CRC Press

    (Publisher)

  Part II

  Basic Properties of Chemicals in the Environment

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  2    Bonds and Molecules: Their Influence on Physical-Chemical Properties in the Environment

  2.1    INTRODUCTION

  The behavior of chemicals in the environment is governed by their physical-chemical properties as well as transformation and degradation processes, which are discussed in Chapter 3 . The physical-chemical properties of compounds include such characteristics as boiling point (bp), melting point (mp), solubility in water, and similar properties. These properties are, in fact, measurements made in the laboratory of environmentally relevant characteristics. For example, compounds with low boiling points evaporate rapidly into the atmosphere, whereas compounds that are highly soluble in water disperse readily in streams and rivers. Thus, an understanding of these properties would be expected to give a clearer perception of how compounds will behave in the environment. This means that the measurement of the physical-chemical properties of a compound could be used to provide an evaluation of its environmental distribution in air, water, sediments, soil, and animals.

  2.2    STATES OF MATTER IN THE ENVIRONMENT

  A cursory examination of the nature of our environment reveals that matter exists in basically three states: solid, liquid, and gas. Solids are present as soil, rocks, and so on, whereas liquids are represented by the great water bodies of the oceans, lakes, and rivers. The gaseous component of the environment is the atmosphere. These states exercise a basic influence on the nature and distribution of all substances, both natural and man-made, in the environment in basic chemical terms. Solids have a definite volume and shape and consist of large numbers of particles that could be atoms, ions, or molecules (Figure 2.1

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