components for polyamides products of propene

Upload: nitty-meya

Post on 03-Apr-2018

228 views

Category:

Documents


1 download

TRANSCRIPT

  • 7/28/2019 Components for Polyamides Products of Propene

    1/58

    Components for polyamides

    Nylon was first produced on an industrial scaleby Du Pont after 1939.

    Polyamides are the products of condensationbetween :

    diamines and dicarboxylic acids, or betweenaminocarboxylic acids

    Polyamides may also be obtained by

    polymerizing lactamsThe characteristic of polyamides structure:CONH units alternating with CH2 chains

  • 7/28/2019 Components for Polyamides Products of Propene

    2/58

    Designation of polyamides

    The use of one figure represents synthesisfrom a single bifunctional compound, e.g.Nylon 6

    Two figures: synthesis from twocomponents, e.g. diamine and dicarboxylicacid

    The values of the digits in the figuressignify the number of carbon atoms ineach component, e.g. Nylon 6,6

  • 7/28/2019 Components for Polyamides Products of Propene

    3/58

  • 7/28/2019 Components for Polyamides Products of Propene

    4/58

    Uses of polyamide

    In synthetic fibres, e.g. clothes,carpets

    In thermoplastics

    Aromatic polyamides oraramides are manufactured

    from terephthalic acid orisophthalic acid

    Aramides are used in flame-resistant fibres, electricalinsulation material and in tire

    cords. Kevlar is used in bullet-proof

    vests, in the lining ofexpensive cars and shutters ofmore expensive cameras

  • 7/28/2019 Components for Polyamides Products of Propene

    5/58

  • 7/28/2019 Components for Polyamides Products of Propene

    6/58

  • 7/28/2019 Components for Polyamides Products of Propene

    7/58

    Dicarboxylic acids

    Adipic acid, suberic acidand sebacic acid are themost widely useddicarboxylic acids in

    industry Most adipic acid is

    obtained from theoxidative cleavage ofcyclohexane in the liquid

    phase and Mn or Co salts(acetate or naphthenate)as catalysts

  • 7/28/2019 Components for Polyamides Products of Propene

    8/58

    The oxidation productsare further oxidized toadipic acid, eitherwith:

    nitric acid andammoniummetavanadate/coppernitrate or

    Air and copper andmanganese acetate

  • 7/28/2019 Components for Polyamides Products of Propene

    9/58

    Uses of adipic acid

    Manufacture of Nylon 6,6

    Starting material for

    hexamethylenediamine

    Component for polyesters

    Converted to esters for use in plasticizers

    and lubricants Hydrogenated to 1,6-n-hexadiol for use in

    polyesters, polyurethanes and HMDA

  • 7/28/2019 Components for Polyamides Products of Propene

    10/58

    1,12-dodecanedioic acid

    The starting material,

    cyclododeca-1,5,9-

    triene, is synthesized

    by the trimerization ofbutadiene with a

    Ziegler catalyst (TiCl4

    and Et2AlCl).

    Ni0 and chromiumcomplexes may also

    be used as catalysts

  • 7/28/2019 Components for Polyamides Products of Propene

    11/58

    Production of C12 dicarboxylic acid

    from cyclododecatriene

    1. Hydrogenation tocycloalkane usingNi catalysts

    2. Mild oxidation to C12cyclicalcohols andketones

    3. Oxidative cleavage

    of the ring, resultingin the formation ofthe dicarboxylic acid

  • 7/28/2019 Components for Polyamides Products of Propene

    12/58

    Uses of C12 dicarboxylic acid

    In polyamide

    In polyesters

    Esterified for use as lubricants

  • 7/28/2019 Components for Polyamides Products of Propene

    13/58

    Hexamethylenediamine

    Cyclohexanone is

    oxidized to caprolactone

    Caprolactone is

    hydrogenated to 1,6-

    hexanediol

    1,6-hexanediol is

    aminated with ammonia

    using a Raney nickel

    catalyst to give 1,6-aminohexanol

  • 7/28/2019 Components for Polyamides Products of Propene

    14/58

    Adiponitrile

    May be obtained by:

    1. Dehydrative

    amination of adipic

    acid with ammonia(C6 + 2N)

    The reaction is

    catalysed by

    phosphoric acid

  • 7/28/2019 Components for Polyamides Products of Propene

    15/58

    2. The Monsanto

    EHD (electro-

    hydrodimerization)

    method involves thehydrogenative

    dimerization of

    acrylonitrile to

    adiponitrile.The net reaction is:

  • 7/28/2019 Components for Polyamides Products of Propene

    16/58

    The steps involved in

    this reductive or

    cathodic dimerization

    are:

  • 7/28/2019 Components for Polyamides Products of Propene

    17/58

    Hydrogenation of adiponitrile

    Adiponitrile can be

    hydrogenated using Co-

    Cu or Fe catalysts to

    produce

    hexamethylenediamine.

  • 7/28/2019 Components for Polyamides Products of Propene

    18/58

    -aminoundecanoic acid

    Precursor for Nylon 11

    Castor oil, the source of ricinoleicacid, is used as the startingmaterial. This is one of the fewexamples of a starting material inindustrial organic chemistry that isnot derived from fossil fuels. Whatis the advantage of this?

    Following transesterification ofglycerol triricinolate withmethanol, the methyl ester ispyrotically cleaved at 3000C toyield a C7 aldehyde and the methylester of undecanoic acid. Thepresence of theOH groupslightly weakens the C-C bondthat is indicated by the dotted line,and this bond is broken atelevated temperatures.

  • 7/28/2019 Components for Polyamides Products of Propene

    19/58

    The methyl ester is

    saponified, then

    converted to 11-

    bromoundecanoic acid by

    peroxide-catalysed HBraddition

    The product is then

    reacted with ammonia,

    producing -aminoundecanoic acid

  • 7/28/2019 Components for Polyamides Products of Propene

    20/58

    Lactams

    -caprolactam, which is the cyclic amide of

    -aminocaproic acid, is the most important

    lactam in industry

    It is used in the manufacture of nylon-6

  • 7/28/2019 Components for Polyamides Products of Propene

    21/58

    The manufacture of-caprolactam

    involves 4 steps

    1. Production ofcyclohexanone.

    Most cyclohexanone

    is produced fromcyclohexane. Analternative routebegins with phenol,which may beconverted tocyclohexanone inone or two steps:

  • 7/28/2019 Components for Polyamides Products of Propene

    22/58

    2. Oxime formation

    using cyclohexanone

    in the presence of a

    hydroxylamine salt:

    The Toray process

    produces oxime by

    photonitrosation of

    cyclohexane:

  • 7/28/2019 Components for Polyamides Products of Propene

    23/58

    3. Conversion of

    cyclohexanone oxime

    into -caprolactam by

    rearrangement in

    sulphuric acid or oleum.The first step forms

    lactam sulphate, which

    upon neutralization with

    ammonia gives the freelactam:

  • 7/28/2019 Components for Polyamides Products of Propene

    24/58

    4. Hydroxylaminesulphate which is usedfor producing the oxime ismanufactured by the

    Raschig process, inwhich ammonium nitrite isreduced with sulphurdioxide to produce thedisulphonate, which is

    then hydrolysed tohydroxylamine sulphate:

  • 7/28/2019 Components for Polyamides Products of Propene

    25/58

    Propene conversion products

    Propylene oxide

    Not as reactive asethylene oxide

    Attempts at producing itby direct oxidation ofpropylene have not beensuccessful

    Propylene oxide ismanufactured by thechlorohydrin process

    which was once the mainroute to the synthesis ofethylene oxide:

  • 7/28/2019 Components for Polyamides Products of Propene

    26/58

    Propylene oxide maybe obtained byindirect oxidation orpropene by radicaloxidation usinghydroperoxides orperoxycarboxylicacids. About 40% of

    propylene oxide isnow produced by thismethod.

  • 7/28/2019 Components for Polyamides Products of Propene

    27/58

    Peracetic acid may be

    produced from acetic

    acid and hydrogen

    peroxide withsulphuric acid as the

    catalyst:

  • 7/28/2019 Components for Polyamides Products of Propene

    28/58

    Secondary products of propylene

    oxide

    Propylene oxide is used to make 1,2-propyleneglycol, dipropylene glycol and propoxylatedproducts

    Propylene glycol is used as an antifreeze and asa brake fluid and in the manufacture of alkydand polyester resins

    Polypropylene glycol, obtained by the reaction

    between propylene oxide and propylene glycol,are used in manufacturing non-ionic surfactants,detergents and emulsiers

  • 7/28/2019 Components for Polyamides Products of Propene

    29/58

    Acetone

    1. Acetone may be obtained by

    direct oxidation of propene by

    the Wacker-Hoechst process

    using PdCl2 as the catalyst.

    Compare this with a similarprocess which converts

    ethylene to acetaldehyde

  • 7/28/2019 Components for Polyamides Products of Propene

    30/58

    2. Acetone may be obtained

    from isopropanol via

    oxidative

    dehydrogenation over Ag

    or Cu catalysts ordehydrogenation over

    ZnO catalysts:

  • 7/28/2019 Components for Polyamides Products of Propene

    31/58

    A method by Shell

    and Du Pont employs

    liquid-phase oxidation

    of isopropanol for theproduction of

    hydrogen peroxide:

  • 7/28/2019 Components for Polyamides Products of Propene

    32/58

    Methyl isobutyl ketone from

    acetone

    Methyl isobutyl ketone is the largest

    volume aldol condensation product from

    acetone

    It is used as a solvent for cellulose

    acetate, alkyd and acrylic resins; as an

    extractant and as the starting material to

    produce hexylene glycol

  • 7/28/2019 Components for Polyamides Products of Propene

    33/58

    1st step: formation ondiacetone alcohol ina base-catalysedaldol reaction

    2nd step: elimination of

    water, catalysed bysulphuric acid orphosphoric acid. Mesityloxide is produced

  • 7/28/2019 Components for Polyamides Products of Propene

    34/58

    3rd step: mesityl oxide

    is hydrogenated to

    methyl isobutyl

    ketone using Ni or Cucatalysts

  • 7/28/2019 Components for Polyamides Products of Propene

    35/58

    Methacrylic acid

    Methacrylic acid is used as a homo- or

    copolymer and as a thickener or for

    finishing

    The methyl ester is its the most widely

    used derivative

    Acetone cyanohydrin is the sole feedstock

    for methacrylic acid

  • 7/28/2019 Components for Polyamides Products of Propene

    36/58

    1. Acetone cyanohydrin isproduced by a base-catalysed addition ofhydrocyanic acid to acetone:

    2. The cyanohydrin is reactedwith sulphuric acid toproduce methacrylic acidamide sulphate, which isthen converted to methylmethacrylate and

    ammonium hydrogensulphate by reaction withmethanol. The product ismethyl methacrylate

  • 7/28/2019 Components for Polyamides Products of Propene

    37/58

    A process designed

    by Mitsubishi

    hydrolyses the

    cyanohydrin to anamide, which is then

    reacted with methyl

    formate to give the

    methyl ester andformamide:

  • 7/28/2019 Components for Polyamides Products of Propene

    38/58

    Uses of methyl methacrylate

    For making Plexiglas,a clear plastic havingconsiderablehardness, resistance

    to fracturing andchemical stability

    As a co-monomer inthe manufacture ofdispersions for paintsand textiles

  • 7/28/2019 Components for Polyamides Products of Propene

    39/58

    Acrolein

    Formerly manufactured bycondensing acetaldehyde withformaldehyde in gaseousphase over sodium silicate:

    Currently all acrolein isproduced by catalytic oxidationof propene over Cu2O/SiC andI2 as the promoter. Note thatthe double bond actives themethyl group, which is

    oxidised. Refer to slide 54 forother examples of methylgroups activated by eithervinylic or aromatic groups

  • 7/28/2019 Components for Polyamides Products of Propene

    40/58

    Uses of acrolein

    Hydrogenation to allyl alcohol

    Reacted with ammonia in thegaseous phase to formpyridine and -picolinemixtures

    As intermediate for themanufacture of acrylic acid andacrylonitrile

    For conversion into methionine(an amino acid)

    For manufacture of1,3-propanediol, an intermediatefor pharmaceuticalcompounds, also used in apolyester for synthetic fibres

  • 7/28/2019 Components for Polyamides Products of Propene

    41/58

    Acrylic acid and its esters

    Ethylene oxide andhydrocyanic acid wereformerly used in theethylene cyanohydrinprocess to formhydroxypropionitrile (inthe presence of a base)

    Hydroxypropionitrile isthen reacted with an

    alcohol or with water andsulphuric acid to producethe ester or the free acid:

  • 7/28/2019 Components for Polyamides Products of Propene

    42/58

    The Reppe process is

    based on the

    carbonylation of

    acetylene in thepresence of water or

    alcohols over a nickel

    tetracarbonyl catalyst,

    producing the freeacid or the ester:

  • 7/28/2019 Components for Polyamides Products of Propene

    43/58

    Today most acrylicacid is obtained fromdirect oxidation ofpropene with air or

    oxygen using amulticomponentcatalyst of mainlymetal molybdates

    with telluriumcompounds ascatalysts:

  • 7/28/2019 Components for Polyamides Products of Propene

    44/58

    Uses of acrylic acid and its esters

    Monomers for homo- and co-polymers

    used for paints and adhesives, in paper

    and textiles and leather processing

    These polymers are superabsorbants,

    having the ability to take up large amounts

    of liquids

  • 7/28/2019 Components for Polyamides Products of Propene

    45/58

    Allyl compounds and its secondary

    products

    These compoundshave the H2C=CH-CH2- functional group

    Hot chlorination ofpropene, in which afree radicalsubstitution takesplace at the allyl

    position, is used tomanufacture allylchloride:

  • 7/28/2019 Components for Polyamides Products of Propene

    46/58

    Uses of allyl chloride

    1. Hydrolysis to allyl

    alcohol

    H2C=CH-CH2-OH

    2. Epoxidation to

    3. Ammonolysis to

    H2C=CH-CH2-NH2

  • 7/28/2019 Components for Polyamides Products of Propene

    47/58

    Epichlorohydrin production

    1. Reaction with

    hypochlorous acid

    in the aqueous

    phase

    2. Elimination of HCl

    using calcium

    hydroxide

    Epichlorohydrin is used to produce glycidyl ethers e.g.

  • 7/28/2019 Components for Polyamides Products of Propene

    48/58

    Epichlorohydrin is used to produce glycidyl ethers e.g.

    bisphenol A glycidyl ether, precursors for epoxy resins. In

    the first step, the epoxide ring breaks to form a chlorohydrin

    ether, but it is reformed upon elimination of HCl by NaOH

  • 7/28/2019 Components for Polyamides Products of Propene

    49/58

    Allyl alcohols and esters

    1. Allyl alcohol fromallyl chloride:

    2. By isomerization ofpropylene oxide

    using lithiumphosphate as thecatalyst

  • 7/28/2019 Components for Polyamides Products of Propene

    50/58

    Uses of allyl alcohols

    Mainly in the manufacture of glycerol.Glycerol is used as a moistening agent,antifreeze, and as a slip additive.

    Glycidol, an intermediate in glycerolsynthesis, is used to synthesizepharmaceutical and cosmetic compounds,and emulsifiers.

    Esters of allyl alcohols, such as maleicand phthalic acid, are used in polymers

    Gl l d ti f ll l

  • 7/28/2019 Components for Polyamides Products of Propene

    51/58

    Glycerol production from allyl

    precursors

    The processes of IG

    Farben (1943) and

    Shell (1948) use allyl

    chloride or itsconversion product

    epichlorohydrin. The

    latter is hydrolysed to

    glycerol using 10%caustic soda:

  • 7/28/2019 Components for Polyamides Products of Propene

    52/58

    Allyl alcohol is

    hydroxylated using

    hydrogen peroxide,

    producing glycidol asan intermediate, using

    tungsten oxide or

    salts of tungstic acid

    as the catalyst:

    Glycerol is used to produce alkyd resin The

  • 7/28/2019 Components for Polyamides Products of Propene

    53/58

    Glycerol is used to produce alkyd resin. The

    reaction between phthalic anyhydride and glycerol

    produces a linear, fusible resin

  • 7/28/2019 Components for Polyamides Products of Propene

    54/58

    Acrylonitrile

    Acrylic acid nitrile or

    acrylonitrile was first

    manufactured in 1930 in

    Germany, then USA. It

    was copolymerized withbutadiene to form a

    synthetic rubber, buna

    N

    The first synthesis (IGFarben) used ethylene

    oxide:

  • 7/28/2019 Components for Polyamides Products of Propene

    55/58

    The method of Bayer utilizedthe addition of HCN toacetylene:

    Acrylonitrile is now producedmainly by the ammoxidation of

    propene. The Sohio process(part of BP) is the mostimportant ammoxidationprocess today. It uses aheterogeneously-catalysedsingle step gas-phase

    oxidation of propene in thepresence of ammonia, air andsteam using Bi2O3.MoO3catalysts in a fluidized bed

    In ammoxidation activated methyl groups

  • 7/28/2019 Components for Polyamides Products of Propene

    56/58

    In ammoxidation, activated methyl groups

    are converted into nitrile groups. Examples

    of such groups:

    Mechanism of ammoxidation: 2 H atoms are first

  • 7/28/2019 Components for Polyamides Products of Propene

    57/58

    Mechanism of ammoxidation: 2 H atoms are first

    abstracted from chemisorbed propene and ammonia, after

    which C3H4 and NH react to give acrylonitrile

  • 7/28/2019 Components for Polyamides Products of Propene

    58/58

    Uses of acrylonitrile

    As a monomer in the synthesis of syntheticfibres, rubbers and plastics, e.g. ABS(acrylonitrile-butadiene-styrene), SAN (styrene-acrylonitrile)

    Electrodimerization of acrylonitrile producesadiponitrile

    Modification of starch and cellulose

    Manufcture dyes and pharmaceutical

    compounds Manufacture of acrylamide, which is used as amonomer to produce polymers used in paints,flocculating agents and resings.