Synthesis of Terpolymer

The presence of three repeating units in terpolymer PI, in the same proportion as in the monomer feed, has been demonstrated by NMR spectrum. DSC analysis has given only one glass transition temperature (Tg) at 17 °C. Molecular weight (Mw) and polydispersity index (Ip) were determined by size exclusion chromatography (Mw = 6000, Ip = 1.4 SEC in THF, standards polystyrene). 

Functionalized Polymers of Malic Acid Stimulate Tissue Repair 

The different preparations have been leading to polymer samples with analogous characteristics. A biological evaluation of terpolymer P4 has been carried out. This polymer has been tested on bone repair and muscle regeneration. 

---

Synthesis of terpolymers has increased in commercial significance over the past few decades. Consider three monomer repeat units entering a polymer backbone chain in a CSTR. There are nine propagation reactions now ... 

Another aspect of interest related to the terpolymerization with the P N systems is the relative rate of the copolymerization of styrene and ethene. The aromatic olefin copolymerizes more rapidly than ethene, but, much more ethene is inserted in the terpolymerization experiment. Therefore, the synthesis of terpolymers with high styrene content using... 

The better understanding of the FTP of fluotinated olefins has allowed synthesis of terpolymers of VDF, HFP, and 1,1,2-ttifluoro-2-pentafluorosulfanylethylene with a good control of molecular weight. ... 

Three 0-substituted B-lactones have been synthesized according to the now well established synthesis route using aspartic acid as chiral precursor . Three alcohols (benzyl, allyl and butyl) were used for the formation of the ester pendent group. Each malolactonic acid ester has been characterized by H and NMR spectra and IR. The synthesis of terpolymer PI has proceeded through anionic ring-opening copolymerization with benzoate tetraethylammonium as initiator (Scheme 1). 

Vinylpyridine (23) came into prominence around 1950 as a component of latex. Butadiene and styrene monomers were used with (23) to make a terpolymer that bonded fabric cords to the mbber matrix of automobile tires (25). More recendy, the abiUty of (23) to act as a Michael acceptor has been exploited in a synthesis of 4-dimethylaminopyridine (DMAP) (24) (26). The sequence consists of a Michael addition of (23) to 4-cyanopyridine (15), replacement of the 4-cyano substituent by dimethylamine (taking advantage of the activation of the cyano group by quatemization of the pyridine ring), and base-cataly2ed dequatemization (retro Michael addition). 4-r)imethyl aminopyri dine is one of the most effective acylation catalysts known (27). 

Further work related to the synthesis of copolymers with either P2VP or P4VP blocks has been reported in the literature. Triblock terpolymers PS-fc-P2VP-fo-PEO were synthesized in THF at - 78 °C by sequential polymerization of styrene and 2VP, initiated by s-BuLi in the presence of IiCl [25]. The living polymer was terminated with EO. The end-hydroxyl group was... 

An allyl samarocene catalyst, [(CMe2C5H4)2SmCl(C3H5)MgCl2(THF)4, was employed for the synthesis of trans-Vl-b-VCL copolymers and poly(fra s-isoprene-co-hex-l-ene)-fr-PCL terpolymers [111]. The copolymerizations... 

The triblock terpolymer polypropylene oxide)-h-poly[2-(dimethylami-no)ethyl methacrylate]-b-poly[oligo(ethylene glycol) methacrylate], PPO-fc-PDMAEMA-fc-POEGMA, was prepared using the PPO macroinitiator followed by the addition of CuCl, HMTETA, and DMAEMA for the polymerization of the second block and finally OEGMA for the synthesis of the final product (Scheme 54) [128]. 

The same heterobifunctional initiator, 2-phenyl-2-[(2,2,6,6-tetramethy-piperidino)oxy] ethyl 2-bromo-2-methyl propanoate, was employed for the synthesis of PMMA-fo-PfBuA-fo-PS triblock terpolymers via the combination of ATRP and NMP [136]. Styrene was initially polymerized through the alkoxyamine function in bulk at 125 °C, leading to PS chains with bromine end groups. Subsequent addition of fBuA in the presence of CuBr/PMDETA provided the PS-fr-PfBuA diblock. Further addition of CuCl, to achieve halogen exchange and MMA yielded the desired triblock copolymer with... 

The oxocarbenium perchlorate C(CH20CH2CH2C0+C104 )4 was employed as a tetrafunctional initiator for the synthesis of PTHF 4-arm stars [146]. The living ends were subsequently reacted either with sodium bromoacetate or bromoisobutyryl chloride. The end-capping reaction was not efficient in the first case (lower than 45%). Therefore, the second procedure was the method of choice for the synthesis of the bromoisobutyryl star-shaped macroinitiators. In the presence of CuCl/bpy the ATRP of styrene was initiated in bulk, leading to the formation of (PTHF-fc-PS)4 star-block copolymers. Further addition of MMA provided the (PTHF-fr-PS-fc-PMMA)4 star-block terpolymers. Relatively narrow molecular weight distributions were obtained with this synthetic procedure. 

By utilizing a combination of RAFT and cationic ROP, the synthesis of [poly(methyl methacrylate)][poly(l,3-dioxepane)][polystyrene] miktoarm star terpolymers was achieved [182], The approach involved the synthesis of PS functionalized with a dithiobenzoate group by RAFT polymerization and subsequent reaction with hydroxyethylene cinnamate (Scheme 98). The newly created hydroxyl group was then used for the cationic ring opening polymerization of 1,3-dioxepane (DOP). The remaining dithiobenzoate group was used for the RAFT polymerization of methyl methacrylate. 

Anionic polymerization techniques were also critical for the synthesis of a model cyclic triblock terpolymer [cyclic(S-fo-I-fr-MMA)] [196]. The linear cctw-amino acid precursor S-fr-I-fr-MMA was synthesized by the sequential anionic polymerization of St, I and MMA with 2,2,5,5-tetramethyl-l-(3-lithiopropyl)-l-aza-2,5-disilacyclopentane as the initiator and amine generator, and 4-bromo-l,l,l-trimethoxybutane as a terminator and carboxylic acid generator. Characterization studies of the intermediate materials as well as of the final cyclic terpolymer revealed high molecular and compositional homogeneity. Additional proof for the formation of the cyclic structure was provided by the lower intrinsic viscosity found for the cyclic terpolymer compared to that of the precursor. 

An interesting way to prepare shock-resistant coatings [381] follows the synthesis of the ABS-terpolymers, e.g. shock-resistant polystyrene, where a soft, elastomeric phase is incorporated in a hard polymer matrix via covalent bonds. Because organic coatings solidify in situ, elastomeric microgels have been synthesized and mixed to a binder which forms the hard matrix phase before the application of this mixture as a coating material. 

Song P, Xiao M, Wang S, Du E, Meng Y (2009) Synthesis and properties of terpolymers derived from carbon dioxide, propylene oxide and phthalic anhydride. Gaofenzi Cailiao Kexue Yu Gongcheng 25(8) ... 

Research Focus Synthesis of amphiphilic terpolymers containing ethylene oxide and (R)-3-hydroxybutyrate and hydrogels containing cyclodextrin. Originality Ongoing 3-year investigation. 

Wamsley, A., Jasti, B., Phiasivongsa, P., and Li, X. Synthesis of random terpolymers and determination of reactivity ratios of IV-carboxyanhydrides of leucine, (1-benzyl aspartate, and valine. J. Polymer Sci. [A] Polymer Chem. 42 317—325, 2004. 

The largest proportion of TFE is used for the polymerization into a variety of PITH homopolymers. It is also used as comonomer in the copolymerization with hexaflu-oropropylene, ethylene, perfluorinated ether, and other monomers and also as a comonomer in a variety of terpolymers. Other uses of TFE are to prepare low-molecular-weight polyfluorocarbons, carbonyl fluoride oils, as well as to form PTFE in situ on metal surfaces,13 and in the synthesis of hexafluoropropylene, perfluorinated ethers, and other oligomers.14... 

Miktoarm star terpolymers of the type ABC have been prepared by several methods. Iatrou and Hadjichristidis reported the synthesis of a miktoarm star consisting of PS, PI and PB branches radiating from the star center [51]. This was achieved using the chlorosilane method and the step by step linking of the different branches to the trichloromethylsilane, which was the linking agent, as shown in Scheme 19. 

Only one case concerning the synthesis of a miktoarm star quaterpolymer has appeared in the literature. It consists of four different branches, namely PS, po-ly(4-methyl styrene) (P4MeS), PI and PB [35]. The reaction sequence for the preparation of this miktoarm star is presented in Scheme 23. The procedure was similar to the one adopted for the synthesis of the ABC-type terpolymers by the chlorosilane method. The characteristic of this method is that two of the arms were incorporated to the linking agent by titration. Consequently the order of addition plays an important role for the preparation of well defined products. PS was chosen to react first with an excess of SiCl4, followed after the evaporation of the excess silane, by the titration with the more sterically hindered P4MeS so that only one arm can be incorporated in the star. The moderately hindered PILi anion was then added by titration, followed by the addition of the fourth arm, which is the least sterically hindered PBLi anion so that complete linking can be achieved. The reaction sequence was monitored by SEC and these results in combination with the molecular and spectroscopic characterization data showed that well defined quaterpolymers were prepared. 

Studies of ethylene-vinyl aromatic monomer polymerizations continue to be published. Chung and Lu reported the synthesis of copolymers of ethylene and P-methylstyrene [28] and the same group extended these studies to produce and characterize elastomeric terpolymers which further include propylene and 1-octene as the additional monomers [29,30]. Returning to the subject of alternative molecular architectures for copolymers, Hou et al. [31] has reported the ability of samarium (II) complexes to copolymerize ethylene and styrene into block copolymers. 

Copolymeirization provides an unique approach to the synthesis of polyfunctional stabilizers. E.g. terpolymers of 4-isopropenyl-2,6-di-terr-butylphenol, methyl methacrylate and 2-(2-hydroxy-5-isopropenyl)-2H-benzotriazole or poly[4-(2,2,6,6-tetramethylpiperidyl) methacrylate-co-4-hydroxy-3,5-di-tert-butyl-benzyl methacrylate] (96), having M 5,400, posses properties of AO and LS [108]. 

Polymerization Catalysed by Acids and Bases. Carbonium ions and carbanions respectively are carriers of the chain transfer in cationic and anionic polymerizations respectively. Ionic polymerization mechanism was exploited for the synthesis of polymeric stabilizers in comparison with the free-radical polymerization only exceptionally. The cationic process was used for the synthesis of copolymers of 2,6-di-tert-butyl-4-vinylphenol with cyclopentadiene and/or for terpolymers with cyclopentadiene and isobutylene [109]. System SnCWEtsAlCla was used as an initiator. Poly(lO-vinylphenothiazin) was prepared by means of catalysis with titanium chlorides [110]. Polymers of 4-[a-(2-hydroxy-3,5-dimethylphenyl)ethyl]-vinylbenzene [111] and 3-allyl-2-hydroxyacetophenone [112] were also prepared under conditions of cationic polymerization. 

Scheme IV. Synthesis of poly(ether-imide-siloxane) elastoplastic terpolymers.

We report firstly in this work, which completes and expands previous investiga-tions the principles involved in the synthesis of the clas of terpolymers and... 

Table 1. Trienes used in the synthesis of ethylene-propylene based terpolymers containing conjugated diene systems... 

---