Phosphorus polyesters provide sustainable flame retardancy to conventional polyesters like PET (poly(ethylene terephthalate)) and PBT (poly(butylene terephthalate)). Their use as a flame retardant additive results in the formation of a classical polymer blend. The morphology of such blends should determine the resulting fire behavior and has therefore to be examined in detail. This study investigates the state of miscibility in blends of standard polyesters (mainly PBT) with phosphorus (co)polyesters mainly using the behavior of the glass transition (Tg). The Tg values were determined by modulated DSC measurements and compared to the ones calculated assuming complete miscibility according to the Fox–Flory concept. The homopolyesters are completely immiscible with each other. Miscibility can be improved by transesterification reactions in the melt as well as by copolyester consisting of segments of PBT or PET and the phosphorus polymer.
WeilEDLevchikSV. Commercial flame retardancy of thermoplastic polyesters – a review. J Fire Sciences2007; 22: 339–350.
5.
GalloEBraunUSchartelB. Halogen-free flame retarded poly(butylene terephthalate)(PBT) using metal oxides/PBT nanocomposites in combination with aluminium phosphinate. Polym Degrad Stab2009; 94: 1245–1253.
6.
BraunUSchartelB. Flame retardancy mechanisms of aluminium phosphinate in combination with melamine cyanurate in glass fibre-reinforced poly(1,4-butylene terephthalate). Macromol Chem Phys2008; 293: 206–217.
7.
ChangY-LWangY-ZBanD-M. A novel phosphorus-containing polymer as a highly effective flame retardant. Macromol Mat Engng2004; 289: 703–707.
8.
PospiechDJehnichenDKomberH. New polymers for tailor-made nanocomposites. J Nanostruct Polymd Nanocomposites2008; 4/4: 62–75.
9.
SatoMEndoSArakiY. The flame-retardant polyester fiber: improvement of hydrolysis resistance. J Appl Polym Sci2000; 78: 1134–1138.
10.
WangCSLinCH. Synthesis and properties of phosphorus-containing PEN and PBN copolyesters. Polymer1999, 40: 747–757.
11.
WangCSLinCHChenCY. Synthesis and properties of phosphorus-containing polyesters derived from 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-hydroxyethoxy phenylene. J Polym Sci, Part A: Polym Chem Ed1998; 17: 3051–3061.
12.
RosescuLPopescuFPetreusO. Synthesis of new polyesters containing phosphorus heterocycles and halogen. Angew Makromol Chem1998; 257: 7–11.
13.
BrehmeSSchartelBGoebbelsJ. Phosphorus polyester versus aluminium phosphinate in poly(butylene terephthalate) (PBT): Flame retardancy performance and mechanism. Polym Degr Stab2011; 96: 875–884.
SchartelBPawlowskiKHLyonRE. Pyrolysis combustion flow calorimeter: a tool to assess flame retarded pc/abs materials?Thermochim Acta2007; 462: 1–14.
16.
SongPCaoZFuS. Thermal degradation and flame retardancy properties of ABS/lignin: Effects of lignin content and reactive compatibilization. Thermochim Acta2011; 518: 59–65.
17.
CretonCKramerEJBrownHRHuiC-J. Adhesion and fracture of interfaces between immiscible polymers: from the molecular to the continuum scale. Adv Polym Sci2002; 156: 53–135.
18.
UtrackiLA. Polymer/polymer miscibility. In: Polymer alloys and blends-thermodynamics and rheology. Munich, New York, Wien: Hanser Publ, 1990.
19.
OhnagaTSatoTNagataS. Miscibility and phase behavior of methyl methacrylate copolymer and polycarbonate blends. Polymer1997; 38: 1073–1079.
20.
FoxTG. Influence of diluent and of copolymer composition on the glass temperature of a polymer system. Bull Am Phys Soc1956; 1: 123.
21.
HäußlerLPospiechDEcksteinK. The influence of multiblock copolymers containing polysulfone and poly(tetramethylene oxide) segments on the phase behavior in polymer blends. Thermochim Acta1999; 339: 87–93.
22.
SablongRDuchateauRKoningCE. Incorporation of a flame retardancy enhancing phosphorus-containing diol into poly(butylene terephthalate) via solid state polymerisation: A comparative study. Polym Degrad Stab2011; 96: 334–341.
23.
PospiechDFischerOKorwitzA. Phosphorus-containing copolyesters with enhanced flame retardancy. In: Proceedings of Polycondensation 2010 Meeting, Rolduc Abbey, The Netherlands, 2010; pp. 26–28.
BartonAFM. Handbook of solubility parameters and other cohesion parameters, 2nd edn. Boca Raton, FL: CRC Pr. LLC, 1991.
28.
PospiechDGottwaldAJehnichenD. Determination of interaction parameters of block copolymers containing aromatic polyesters from solubility parameters obtained by solution viscosities. Colloid & Polym Sci2002; 280: 1027–1037.
29.
Van KrevelenDW. Cohesive properties and solubility. In: Properties of polymers. Their correlation with chemical structure, their numerical estimation and prediction from additive group contributions. Amsterdam, Oxford, New York, Tokyo: Elsevier1990, Chapter 7. pp. 196–197.
30.
LeverdFFradetA. Study of model eseterifications and of polyesterifications catalyzed by titanium derivatives. Eur Polym J1987; 23: 695–698.
31.
PompeG. Influence of transesterification on the thermal properties of PC/PBT blend – miscibility of PC and PBT. Recent Res Dev Polym Sci1997; 1: 109–147.
32.
PilatiFMarianucciEBertiC. Study of the reactions occurring during melt mixing of poly(ethylene terephthalate) and polycarbonate. J Appl Polym Sci1985; 30: 1267–1275.
33.
BertiCBonoraVPilatiF. Reactive blending of poly(ethylene terephthalate) and polycarbonate. 1, A reappraisal of the reactions occurring during melt mixing. Makromol Chem1992; 193: 1665–1677.
34.
NoolandiJShiA-C. Reinforcement of polymer interfaces with random copolymers: an example of interfacial self-stitching?Phys Rev Lett1992; 74: 2836–2837.
35.
ChengSZDPanRWunderlichB. Thermal analysis of poly(butylene terephthalate) for heat capacity, rigid amorphous content, and transition behavior. Makromol Chem1988; 189: 2443–2458.
KöpplTWolff-FabrisFAltstädtV. Influence of solid and polymeric halogen-free retardant on the structure-property relationships of poyl(butylene terephthalate). In: Proceedings 13th European Meeting on Fire Retardant Polymers, June 2011, Alessandria, Italy, 2011, p. 37.
