Untersuchungen zur Festphasenpolykondensation von Polytetramethylenterephthalat

Abstract

DDR -756 Wilhelm-Pieck-Stadt Cuben Unter Anwendung eines Gaschromatographen wurde die Festphasenpolykondensation von Polytetramethylenterephthalat im Temperaturbereich von 170 bis 215°C in stromendem Wasserstoff durchgefuhrt. Der EinfluR von Molmasse, Reaktionstemperatur und Reaktionszeit wird untersucht und diskutiert. Mccneaosanus IC msepao$aanofi nonu?coidexeayuu nodaumempawemunenmepe~manama I ' a 3 x p o~a~o r p a @ i r e c~~1~ MeToAoM EisyqaJracb ~s e p~o + a a~a~i nonEiKoH,qeHcawm nonHTeTpaMeTEineHTepe~TanaTa B TeKYIIJeM BOAOpOAe B TeMnepaTypHOM EiHTepBane OT 170 A 0 215°C. klCCJIeAOBan0Cb EI 06cym~anocb BJIARHAe MOJIeKyJIRpHOfi MPCCbI, a TaKHle TeMnepaTypbI Ei npOAOn~MTeJIbHOCTEI PeaKqEiEi. Investigations on the solid state polycondensation of poZy(tetramcJthy1ene terephthalate)Using gas chromatography the solid state polycondensation of poly(tetramethy1ene terephthalate) was carried out in flowing hydrogen in the temperature range from 170 to 215°C. The influence of molecular weight, reaction temperature and reaction time was investigated and discussed.

Solid-State Modification of Poly(butylene terephthalate) with a Bio-Based Fatty Acid Dimer Diol Furnishing Copolyesters with Unique Morphologies

“…The influences of various reaction parameters, viz. temperature, ,, type of gas or gas flow rate through the solid particles, ,, and particle size, ,,− on the SS-PC process were studied extensively. The aim of the majority of the previously conducted studies was to increase the efficiency of the molecular weight increase during the SS-PC process of a “homopolyester”.…”

Incorporation of Isosorbide into Poly(butylene terephthalate) via Solid-State Polymerization

“…9 High molecular weight can only be reached through polymerization in the solid state at temperatures that are 10-40 °C below the melting temperature of PBT in the presence of a nitrogen flow or vacuum. 10 During the solid-state polymerization (SSP) of PBT below the melting point of the crystals but relatively far above the glass-transition temperature of the amorphous part, the polymer chains in the amorphous phase are sufficiently mobile to undergo transesterification reactions with a non-volatile diol to be incorporated into the main chain, whereas the volatile products (1,4-butadiol, water) diffuse out of the PBT particles and leave the reactor with the help of an inert gas stream or vacuum. Whereas various copolymers were already obtained via this process from semicrystalline, oligomeric blends of polycondensates, 11 the incorporation of monomers has been limited so far.…”

“…In fact, even in the absence of isosorbide, PBT with a molecular weight of >25 000 g·mol −1 is relatively difficult to obtain by melt polycondensation . High molecular weight can only be reached through polymerization in the solid state at temperatures that are 10−40 °C below the melting temperature of PBT in the presence of a nitrogen flow or vacuum . During the solid-state polymerization (SSP) of PBT below the melting point of the crystals but relatively far above the glass-transition temperature of the amorphous part, the polymer chains in the amorphous phase are sufficiently mobile to undergo transesterification reactions with a non-volatile diol to be incorporated into the main chain, whereas the volatile products (1,4-butadiol, water) diffuse out of the PBT particles and leave the reactor with the help of an inert gas stream or vacuum.…”

Chemical kinetics and diffusion in poly(butylene terephthalate) solid‐state polycondensation: Experiments and theory

“…Relevant examples are recognized in poly(ethy1ene terephthalate) (PET) and in poly(buty1ene terephthlate) (PBT). [1][2][3][4][5][6][7][8][9] Typically the polymer is heated up to temperature ranges which enhance propagation reactions, usually up to 20-50°C below T,,,, in order to avoid particle sticking; then the polymer is kept under vacuum or in an inert gas stream which strips out the volatile condensation products. The overall process kinetics are thus influenced by the rate of all the simultaneous reactions and by the rate of diffusion of the low molecular weight compounds.…”

“…In the case of PBT here considered, postpolymerization was previously studied in fine polymer particles so that the effects of diffusion were disregarded. 5,6,8 Several chemical reactions can occur in the usual operating conditions, but only for a few of them are detailed studies available and a general consensus was achieved about their kinetics; for other reactions, on the other hand, either there is no universal agreement on the relevant kinetic mechanisms, or little attention has been payed to a quantitative kinetic description.…”