1,4-butane diol structure

The role of the molecular structure of the alcohol or the molecule considered. For instance, isomer butane diols on gold C2-C6 polyols on Pt and gold. ... 

As polyurethane intermediates react rapidly and stoichiometrically with each other, a system of nomenclature is widely used to describe the structure of individual block copolymers. Suppose, for example, a typical polyurethane consisted of polycaprolactone,4,4 -diphenylmethane diisocyanate, and 1,4-butane diol, present in the molar ratio 1 3 2, then such a polymer is reported as a 1 3 2 block copolymer and this represents a simple, convenient and rapid method of identifying the basic urethane polymer structure. The ratio of each component in the block copolymer has a dramatic effect on its properties, as shown by the data in Table 2.2. 

These presently form the basic structure of the majority of commercially available cast, thermoplastic and millable elastomer systems with the most used chain extenders being 3,3 -dichloro-4,4 -diaminodiphenyl methane (MOCA) and 1,4-butane diol (BDO). Many well-known two-component castable commercial systems became established upon such technology with, in some cases, the trade names becoming almost generic terms, e.g. Adiprene (Du Pont and now Uniroyal) and Cyanaprene (Cyanamid). 

A model for the chain conformation and packing of diphenyl methane 4,4 -di-isocyanate butane diol (M) hard segments in polyurethane elastomers" has been made based on the single crystal structure of the monomer unit, Me-M-Me in which... 

Time of flight secondary ion mass spectrometry (SIMS) has been used to carry out structure characterizations on polyurethanes based on diols (ethylene glycol, 1,4 butane diol, 1.6-hexanediol) and diisocyanates, (methylene disocyanate, toluene diisocyanate, dicyclohexylmethane diisocyanate). Fragments and oligomers produced in the m/z range 500 - 3200 enabled characterizations to be carried out. 

Chiral diphosphites based on (2R,3R)-butane-2,3-diol, (2R,4R)-pentane-2,4-diol, (25, 5S)-hexane-2,5-diol, (lS -diphenylpropane-hS-diol, and tV-benzyltartarimide as chiral bridges have been used in the Rh-catalyzed asymmetric hydroformylation of styrene. Enantioselectivities up to 76%, at 50% conversion, have been obtained with stable hydridorhodium diphosphite catalysts. The solution structures of [RhH(L)(CO)2] complexes have been studied NMR and IR spectroscopic data revealed fluxional behavior. Depending on the structure of the bridge, the diphosphite adopts equatorial-equatorial or equatorial-axial coordination to the rhodium. The structure and the stability of the catalysts play a role in the asymmetric induction.218... 

Thermoplastic copolyester elastomers are generally block copolymers produced from short-chain aliphatic diols, aromatic diacids, and polyalkylene ether-diols. They are often called polyesterether or polyester elastomers. The most significant commercial product is the copolymer from butane-1,4-diol, dimethyl terephthalate, and polytetramethylene ether glycol [25190-06-1/, which produces a segmented block copolyesterether with the following structure. 

Structure, properties. PTHF is a linear elastomer with the following repeat unit [—OCH2CH2CH2CH2—]. Poly(tetrahydrofuran) is also named poly(tetramethylene oxide) (PTMO) and the official name is poly(-oxy-1,4-butane diyl). For PTHF diols the usual names are poly(tetrameth-ylene ether) glycols (PTMEG). 

Ritter et al. [147-155] have been studying side chain poiyrotaxanes. They synthesized side chain poiyrotaxanes by amide coupling of polymer-carrying carboxylic acid moieties with various semirotaxanes of methylated /l-CD(s) and an axle bearing an amine group at one end [147-154]. These works have been reviewed in an excellent review by Raymo and Stoddard [78]. Ritter et al. [155] reported recently a new type of side chain polyrotaxane. They polymerized inclusion complexes of di(meth)acrylates of butan-l,4-diol and hexan-l,6-diol with a-CD and with methylated /1-CD using a redox initiator system in aqueous media, and characterized the polyrotaxane structure by IR and glass-transition temperature measurements. 

To rationalize the effect of structure and substituents on the acid- or base-catalyzed loss of water from a,/S-dihydroxy-substituted radicals, the complementary techniques of pulse-radiolysis and ESR spectroscopy have been employed in a kinetic study of the dehydration of a variety of a,/9-dihydroxyalkyl radicals [ CR (0H)CR R 0H] into the corresponding carbonyl-conjugated radicals [ CR R C(0)R ]. The overall rates of proton-catalyzed dehydration, as revealed by steady-state (ESR) and time-resolved (pulse-radiolysis) experiments, indicate the importance of the electronic effects of substituents (contrast values of 1.2 x 10 and 9.8 X 10 s for the radicals from cyclohexane-1,2-diol and butane-2,3-diol, respectively, with that for the radicals from erythritol of 4.2 x 10 m s ). Time-resolved experiments enable information to be obtained about the generation of the protonated species [ CR (0H)CR R 0H2 ] and the loss of water from this intermediate. 

The Veriflex PSMP is a two-part resin system. Part A is composed of styrene, divinyl benzene and vinyl neodecanoate. Part B is composed of benzoyl peroxide. The chemical stmcture for each component has been shown in Figure 3.2. The thermoplastic copolyester (CP) is composed of isopthalic acid, terepthalic acid and butane-1,4-diol. The chemical structure for each component is shown in Figure 6.11. 

Polybutylene Terephthalate (PBT). With the expiration of the original PET patents, manufacturers pursued the polymerization of other polyalkene teiephthalates, particularly polybutylene terephthalate (PBT). The polymer is synthesized by reacting terephthalic acid with butane 1,4-diol to yield the structure shown in Fig. 2.16. 

The enzymatic synthesis of peptides (Scheme 6.24) from which proteins can be constructed is not so limited, and chemical synthesis has an even wider application, but these are not yet suitable techniques for manufacture. Moreover, there are no general methods for building the peptides into full protein structures. Nevertheless, enzymes do have a role in the manufacture of peptides themselves. In a mixture of butan-l,4-diol and water, trypsin will catalyse the exchange of the carboxy-terminal alanine of porcine insulin with threonine t-butyl ester (Scheme 6.25). The reaction is essentially a transpeptidation in which the acyl group of lysine is transferred from one amino group on alanine to another on the threonine. This converts porcine insulin into the ester of the human hormone, and a simple deprotection yields one of the commercial products. 

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