Amino End-Functionalized Polyethylenes and Corresponding

Article Cite This: Macromolecules XXXX, XXX, XXX-XXX

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Amino End-Functionalized Polyethylenes and Corresponding Telechelics by Coordinative Chain Transfer Polymerization Winnie Nzahou Ottou, Sébastien Norsic, Islem Belaid, Christophe Boisson,* and Franck D’Agosto* Laboratoire Chimie Catalyse Polymères et Procédés (C2P2), Equipe LCPP Bat 308F, CNRS UMR 5265, Université de Lyon, Univ. Lyon 1, CPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France S Supporting Information *

ABSTRACT: Di(1-(propyl)-2,2,5,5-tetramethyl-1-aza-2,5-disilacylopentane)magnesium was synthesized and used as chain transfer agent for the ethylene polymerization in the presence of a neodymocene precursor. The polymerization was shown to be governed by a catalyzed chain growth process (CCG) on magnesium, allowing the quantitative formation of ammonium or amine functionalized polyethylene (PE) chains. The structure of these chains was shown by 1H and 13C NMR analyses. MALDI-ToF mass spectrometry was successfully used to confirm the structure predicted by the CCG mechanism. The additional formation of telechelic PE chains carrying an ammonium and either a diethyldithiocarbamate or an iodo moiety as end groups was shown after a simple deactivation of the polymerization medium with disulfiram or molecular iodine, respectively.

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transfer (RAFT) process in radical polymerization.9 Welldefined polyethylene chains with molar masses fixed by the ratio of ethylene consumed over the concentration of CTA can thus be formed under truly catalytic conditions. Mortreux et al.10 reported the CCG of ethylene on magnesium using lanthanidocene complexes in association with a dialkylmagnesium (R-Mg-R) acting as both cocatalyst and CTA. The formation in the reactor of a dipolyethylenylmagnesium compounds (R-PE-Mg-PE-R) and the subsequent reactivity of the carbon− magnesium bonds were exploited for the design of a variety of ω-end-functional polyethylene chains.11 Functionalities as high as 95% were achieved by deactivation of the polymerization medium with the appropriate compounds and sometimes additional steps of simple chemistry.12−19 Among the different functionalities introduced on the ω-end chain, amine could be obtained starting from iodo polyethylene via substitution of the iodine atom with an azide and reduction of the azido into an amine.20−22 We investigated the possibility to further employ functionalized CTAs to avoid this although successful often tedious multistep chemistry. Indeed, introducing a functionality on the chains via the initiating R group of the CTA was very appealing

INTRODUCTION Polyolefins, mainly polypropylene (PP) and polyethylene (PE), are the most produced thermoplastics.1 The readily available monomers they are made from together with the well-established and robust associated polymerization processes make this class of polymers a firm favorite of commodity plastics in our everyday life.2 To enlarge the already wide scope of these very apolar polymers, the introduction of functional groups on polyolefins has always been a target. This, however, is associated with important challenges, the main one being the use of industrially relevant strategies.3 Indeed, the available techniques to achieve this goal often fail in providing tools that are easily scalable. Recently, the concepts of catalyzed chain growth4−6 or coordinative chain transfer polymerization3,7 in which a transition metal complex is used as a polymerization catalyst in association with a second organometallic species used as chain transfer agent (CTA) provided an efficient tool to control the growth of polyethylene chains and to their further functionalization. This was possible by the establishment of a reversible degenerative chain transfer between the transition metal center where the polyethylene chain is growing and the main group metal-based CTA where polyethylene chains can momentarily rest. In the presence of a catalytic amount of transition metal complex, this chain transfer reaction is fast compared to propagation and a pseudo-living behavior of the polymerization is observed8 comparable to a reversible addition−fragmentation chain © XXXX American Chemical Society

Received: June 30, 2017 Revised: September 15, 2017

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DOI: 10.1021/acs.macromol.7b01396 Macromolecules XXXX, XXX, XXX−XXX

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Macromolecules

polymerizations. In addition, we recently demonstrated the activating effect of di-n-butyl ether (Bu2O) on the ethylene polymerization using [(C5Me5)2NdCl2Li(OEt2)2]/MgR2 catalytic system.8,27 A Bu2O solution of 3 was thus used for the polymerization. Titration of the magnesium content was performed using no-deuterium 1H NMR spectroscopy in a “lock-off” mode (see the Supporting Information for details).38 Synthesis of α-Amino Functionalized Polyethylenes. The ability of 3 to act as a cocatalyst and an efficient CTA was first evaluated by conducting ethylene polymerizations at 75 °C in toluene using [(C5Me5)2NdCl2Li(OEt2)2] as precursor (Mg/Nd molar ratio of 140) (Scheme 2). The first

as a means to optimize the rate of functionalization of the chains. This also allowed accessing an unprecedented strategy to telechelic polyethylenes23−25 by additionally taking advantage of the abovementioned established reactivity of R-PE-Mg-PE-R toward electrophiles. The challenge here is to adequately tune the nature of the functional groups introduced on the CTA to keep both the catalytic activity and the reversible chain transfer efficiency. Bis(pentamethylcyclopentadienyl)-neodymium catalysts have shown no propensity to incorporate α-olefins into predominantly PE chains,26 which raised the possibility of employing dialkenylmagnesium CTAs in polyethylene CCG. This provided vinyl-functionalized polyethylene chains and for the first time starting from ethylene and using coordination insertion polymerization, their corresponding hetero27 and homobifunctional28 telechelic polyethylenes. In the present paper, we describe a new chain transfer agent carrying a protected amine group. The potentialities of this CTA in a polyethylene CCG process are evaluated in the presence of [(C5Me5)2NdCl2Li(OEt2)2] complex. The challenge addressed in this paper is twofold. The first one is to produce amino end-functionalized polyethylene chains for the first time directly during the polymerization. The second one is to enlarge the scope of this CTA to the design of new telechelic polyethylenes.29

Scheme 2. CCG Polymerization of Ethylene Using a Neodymocene Complex and the Amino-Based Dialkylmagnesium 3 as Cocatalyst and Chain Transfer Agent

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RESULTS AND DISCUSSION α-Olefins carrying trialkylsilyl30,31 or alkylaluminum32 protected amine have already been successfully polymerized by catalytic coordination insertion polymerization. We thus anticipated that dialkylmagnesium compounds containing alkylsilyl protected amine moieties would be tolerated by the neodymocene catalyst. If so, they might therefore be excellent CTAs for polyethylene CCG to provide the target amino end-functionalized PE (PE-NH2) directly after the work-up procedure. Synthesis of the Amino-Based Dialkylmagnesium 3. Dialkylmagnesium is often obtained by displacement of the Schlenk equilibrium of the corresponding alkylmagnesium bromide in ethereal solution.33−36 In a first step, 1-(3-bromopropyl)-2,2,5,5tetramethyl-1-aza-2,5-disilacylopentane (1) (Scheme 1) was isolated

goals were to identify if the polymerization provides a final polymer featuring an amino end group. After consuming the desired quantity of ethylene (theoretical molar masses MnTheo determined considering the amount of 3 used and the formation of two PE chains per Mg center; MnTheo = 2200 g mol−1), the polymerization medium was cooled down and quenched with acidic methanol (MeOH/HCl) to simultaneously deactivate the targeted di(1-(polyethylenyl)-2,2,5,5-tetramethyl-1aza-2,5-disilacylopentane)magnesium and deprotect the amino group. Polyethylene was then recovered by simple filtration. The final polymer was analyzed by 1H and 13C NMR (Table 1, entry 1; Figures 1a and 1b, respectively).

Scheme 1. Synthesis of Alkylmagnesium Bromide 2 and Dialkylmagnesium 3 from 1-(3-Bromopropyl)-2,2,5,5tetramethyl-1-aza-2,5-disilacylopentane (1)

Table 1. Molar Mass Characteristics and Yields of α-Ammonium Functionalized Polyethylene (PE-NH3+Cl−) entry

yield (g)

MnTheo (g mol−1)

MnSEC (g mol−1) (Đ)

MnNMR (g mol−1)

%NMR CH2N

1 2 3

12.5 12.4 11.6

2200 4200 4250

1200 (2.3) 1900 (1.8) 2700 (1.5)

2300 4400 4700

97 94 95

The resonances of the methylene protons (between 1.0 and 1.5 ppm Figure 1a) of the main PE chain and the presence of signals at 2.86 and 1.74 ppm assigned to methylene in α and β positions of an ammonium group (resonance at 8.45 ppm) clearly showed that the obtained structure was consistent with the expected one, PE-NH3+Cl−. The presence of trace amount of chains terminated with a vinyl group was also observed (δ = 4.8−5.8 ppm) and resulted from β-H elimination reaction.20,27 Considering these different chain end assignments and the integrations of the corresponding resonances, a functionality of 97% was calculated (see the Supporting Information for the

by reacting 1,1,4,4-tetramethyl-1,4-dichloro-1,4-disilabutane with 3-bromopropylamine hydrobromide (see Supporting Information Figure S1). Di(1-(propyl)-2,2,5,5-tetramethyl-1-aza-2,5disilacylopentane)magnesium (3) was further successfully obtained by addition of 1.5 equiv of dioxane to a THF solution of 1-(propyl)-2,2,5,5-tetramethyl-1-aza-2,5-disilacylopentane magnesium bromide (2) obtained from 1. 3 was obtained with a 70% yield. The unavoidable presence of the Wurtz coupling product37 in the final product was shown (16%, Figure S2), but that did not disturb the course of the B


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Figure 1. 1H (a) and 13C (b) NMR spectra (TCE/C6D6, 363 K) of α-ammonium end-functionalized polyethylene (Table 1, entry 1).

used method). This promising result was confirmed by 13C NMR analyses. The spectrum (Figure 1b) features the presence of a carbon at 39.9 ppm adjacent to the ammonium end-group introduced. A molar mass MnNMR of 2300 g mol−1 was determined from the 1H NMR spectrum (MnNMR in Table 1, see the Supporting Information for the calculation method) that was in good agreement with the theoretical value calculated from the mass of obtained polyethylene and considering the formation of two polymer chains per Mg (MnTheo = 2200 g mol−1). High temperature size-exclusion chromatography (HT-SEC) analysis of the same sample was performed (Figure S3). A molar mass MnSEC of 1200 g mol−1 and a broad molar mass distribution (Đ = 2.3) were obtained (Table 1). However, the poor quality of the chromatogram strongly suggests that interactions were taking place between the introduced end group and the stationary phase of the column, making PENH3+Cl− hardly characterizable by this technique. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF MS) analysis is usually not appropriate for PE chains that lack cationizable groups. In our previous investigations to functionalize PE, MALDI-ToF MS was sometimes successfully employed since the introduction of polar groups eased the chain cationization which is a prerequisite for this kind of analysis. As an example, PE-NH2 chains obtained by CCG followed by a multistep chemistry20 were easily cationized and successfully analyzed by MALDIToF MS.22 This result prompted us to analyze by MALDI-ToF MS the already cationized PE-NH3+Cl− obtained with the present one-pot method. The MALDI-ToF MS analysis revealed the presence of one population (m/z = 60.08 + 28.03n, where 60.08 is the exact molar mass of the end-groups H− and −CH2CH2CH2-NH3+, Figure 2)

Figure 2. MALDI-ToF mass spectrum of α-ammonium functionalized polyethylene (Table 1, entry 1).

for which the isotopic distribution features a structure consistent with PE-NH3+Cl−. The very good consistency between the previous characterization techniques (1H and 13C NMR and MALDI-ToF MS) with respect to the targeted PE-NH3+Cl− structure showed the successful use of 3 as CTA for the polymerization of ethylene according to a CCG process. Primary amines are of broad utility in organic chemistry. To recover the non-protonated primary amine form (PE-NH2), deactivation with crude methanol was initially performed. However, incomplete deprotection of the amine group was observed. The above obtained PE-NH 3 + Cl − was thus deprotonated in THF at room temperature for 15 h with a 1 M THF solution of tBuOK. The 1H and 13C NMR spectra of the resulting polymer (Figures 3a and 3b, respectively) confirmed the quantitative formation of PE-NH2. The HT-SEC chromatogram of PE chains bearing an amine end group clearly demonstrated that this analytical technique is also not suitable for these samples as discussed above for PE-NH3+Cl− (Figure S3). The same procedure could be reproduced to target higher molar mass PE (Table 1, entries 2 and 3, and Figure S4). A PENH3+Cl− with MnNMR = 4400 g mol−1 and a functionality of 94% was obtained. Again, a good agreement between theoretical (MnTheo = 4200 g mol−1) and experimental molar masses highlighted the efficiency of the CCG of ethylene on magnesium using 3. The successful use of 3 as an efficient cocatalyst and CTA in ethylene polymerization mediated by [(C5Me5)2NdCl2Li(OEt2)2] C


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Figure 3. 1H and 13C NMR spectra (TCE/C6D6, 363 K) of α-amine end-functionalized polyethylene (Table 1, entry 1).

Figure 5. 1H (a) and 13C (b) NMR spectra (TCE/C6D6, 363 K) of α-ammonium, ω-dithiocarbamate end-functionalized polyethylene (−Cl+H3N-PE-CH2-S(CS)NEt2).

complex was further demonstrated by following the evolution of molar masses determined by 1H NMR versus productivity (see Supporting Information Table S1 and Figure 4).

targeted telechelic polymer −Cl+H3N-PE-SC(S)NEt2 telechelic polymer. A quantitative functionalization was determined by 1H NMR, and MnNMR was 1500 g mol−1, in good agreement with the expected value (MnTheo = 1300 g mol−1). The presence of the dithiocarbamate chain end was further shown by FT-IR analyses which show absorbance characteristic of the N−CS bond stretching mode at ν = 1414 cm−1 (see Figure S6). The MALDI-ToF MS spectrum (Figure 6) revealed the presence of a main population (P1) corresponding to the expected −Cl+H3N-PE-SC(S)NEt2 structure with m/z = 179.07 + 28.03n, where 179.07 is the exact molar mass of the end-groups (+H3N-CH2− and −S-C(S)N(Et)2). The side population P2 at minus 4 g mol−1 from P1 was ascribed to the thiol equivalent, presumably formed during the MALDI-ToF analysis as previously shown.13 Similar to the previously described procedure to obtain iodo polyethylene,20−22 an α-ammonium-ω-iodo telechelic polyethylene −I+NH3-PE-I was also prepared by adding iodine to the solution of di(1-(polyethylenyl)-2,2,5,5-tetramethyl-1aza-2,5-disilacylopentane)magnesium. After the reaction, the as-obtained polymer was precipitated in a H2O/HI solution instead of MeOH/HCl to avoid halogen exchange. The experimental molar masses determined by 1H NMR analysis (MnNMR = 2100 g mol−1) was in good agreement with the theoretical value (MnTheo = 1700 g mol−1), in accordance with a controlled polymerization. Unfortunately, no signal was obtained when analyzing this telechelic polyethylene by MALDI-ToF under the same conditions as the ones used above. Quantitative functionalization was nevertheless demonstrated by both 1H and 13C NMR analyses (Figure 7).

Figure 4. Evolution of MnNMR versus productivity (according to Table S1).

Molar masses increase linearly with productivity. This confirms the pseudo-living behavior of the polymerization and the efficient installation of a degenerative transfer with this new CTA (3). Synthesis of Telechelic Polyethylenes. −Cl+H3N-PESC(S)NEt2 telechelic polyethylene was additionally synthesized by reacting di(1-(polyethylenyl)-2,2,5,5-tetramethyl-1-aza-2,5disilacylopentane)magnesium and disulfiram at 75 °C in a method similar to that previously used in our laboratories to prepare PE-SC(S)NEt2 from PE-Mg-PE.13 Both 1H and 13C NMR analyses (Figure 5) demonstrated the successful ω-functionalization with a dithiocarbamate group and the production of the D


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CONCLUSIONS In conclusion, a new dialkylmagnesium chain transfer agent containing a 2,2,5,5-tetramethyl-1-aza-2,5-disilacylopentane moiety was synthesized and was shown to efficiently install a reversible chain transfer during ethylene polymerization in the presence of [(C5Me5)2NdCl2Li(OEt2)2] precursor. The presence of a protected amine group tolerated during the whole process allows producing well-defined polymer chains that upon deactivation using acidic methanol provide unique ammoniumterminated polyethylene chains in one step. The easy deprotonation of these chains leads to amine end-functionalized polyethylenes. These quantitative functionalizations allow the formation of telechelic polyethylenes featuring one ammonium end group. This system further expands the potentiality of using these polyolefins building blocks in various fields of material science.

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.macromol.7b01396. Materials and characterization data for all compounds; experimental procedures for organomagnesium syntheses and functionalized polymers; additional NMR spectra of PE-NH3+Cl− (higher molar masses and final polymer from kinetics); HT-SEC chromatogram of (−Cl+H3N-PE and H2N-PE); FTIR spectrum of telechelic polymer − + Cl H3N-PE-SC(S)NEt2 (PDF)

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Figure 6. MALDI-ToF mass spectrum of α-ammonium, ω-dithiocarbamate end-functionalized polyethylene (−Cl+H3N-PE-SC(S)NEt2).

AUTHOR INFORMATION

Corresponding Authors

*(F.D.) E-mail [email protected]. *(C.B.) E-mail [email protected]. ORCID

Christophe Boisson: 0000-0002-7909-901X Franck D’Agosto: 0000-0003-2730-869X Author Contributions

W.N.O. and S.N. contributed equally. Funding

The authors received funding from the French National Agency for Research (ANR SUPRA PE 13-BS08-0006 and ANR LISIP15-LCV4-005) and from the French government’s FUI program (FUI REPEAT 2). Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS The authors thank the NMR Polymer Center of Institut de Chimie de Lyon (FR5223) for assistance and access to the NMR facilities, Olivier Boyron and Manel Taam (C2P2) for HT-SEC analyses, and Frédéric Delolme (IBCP) for MALDI ToF MS analyses.

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REFERENCES

(1) Baier, M. C.; Zuideveld, M. A.; Mecking, S. Post-Metallocenes in the Industrial Production of Polyolefins. Angew. Chem., Int. Ed. 2014, 53, 9722−9744. (2) Hustad, P. D. Frontiers in Olefin Polymerization: Reinventing the World’s Most Common Synthetic Polymers. Science 2009, 325, 704− 707.

Figure 7. 1H (a) and 13C (b) NMR spectra (TCE/C6D6, 363 K) of α-amino, ω-iodo end-functionalized polyethylene (−I+H3N-PE-I). E


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(22) Damiron, D.; Mazzolini, J.; Cousin, F.; Boisson, C.; D’Agosto, F.; Drockenmuller, E. Poly(ethylene) brushes grafted to silicon substrates. Polym. Chem. 2012, 3, 1838−1845. (23) Jian, Z.; Falivene, L.; Boffa, G.; Sánchez, S. O.; Caporaso, L.; Grassi, A.; Mecking, S. Direct Synthesis of Telechelic Polyethylene by Selective Insertion Polymerization. Angew. Chem., Int. Ed. 2016, 55, 14378−14383. (24) Witt, T.; Häußler, M.; Kulpa, S.; Mecking, S. Chain Multiplication of Fatty Acids to Precise Telechelic Polyethylene. Angew. Chem., Int. Ed. 2017, 56, 7589−7594. (25) Makio, H.; Ochiai, T.; Mohri, J.; Takeda, K.; Shimazaki, T.; Usui, Y.; Matsuura, S.; Fujita, T. Synthesis of Telechelic Olefin Polymers via Catalyzed Chain Growth on Multinuclear Alkylene Zinc Compounds. J. Am. Chem. Soc. 2013, 135, 8177−8180. (26) Jeske, G.; Lauke, I H.; Mauermann, H.; Swepston, P.N.; Schumann, H.; Marks, T.J. Highly Reactive organolanthanides. Systematic Routes to and Olefin Chemistry of Early and Late Bis(pentamethylcyclopentadienyl) 4f hydrocarbyl and Hydride Complexes. J. Am. Chem. Soc. 1985, 107, 8091−8103. (27) German, I.; Kelhifi, W.; Norsic, S.; Boisson, C.; D’Agosto, F. Telechelic Polyethylene from Catalyzed Chain-Growth Polymerization. Angew. Chem., Int. Ed. 2013, 52, 3438−3441. (28) Norsic, S.; Thomas, C.; D’Agosto, F.; Boisson, C. Divinyl-EndFunctionalized Polyethylenes: Ready Access to a Range of Telechelic Polyethylenes through Thiol−Ene Reactions. Angew. Chem., Int. Ed. 2015, 54, 4631−4635. (29) Todd, A. D.; McEneany, R. J.; Topolkaraev, V. A.; Macosko, C. W.; Hillmyer, M. A. Reactive Compatibilization of Poly(ethylene terephthalate) and High-Density Polyethylene Using Amino-Telechelic Polyethylene. Macromolecules 2016, 49, 8988−8994. (30) Schneider, M. J.; Schäfer, R.; Mülhaupt, R. Aminofunctional linear low density polyethylene via metallocene-catalysed ethene copolymerization with N,N-bis(trimethylsilyl)-1-amino-10-undecene. Polymer 1997, 38, 2455−2459. (31) Zhang, M.; Kim, H. K.; Chalkova, E.; Mark, F.; Lvov, S. N.; Chung, T. C. M. New Polyethylene Based Anion Exchange Membranes (PE−AEMs) with High Ionic Conductivity. Macromolecules 2011, 44, 5937−5946. (32) Kandil, U. F.; Amer, N. M.; Shaker, N. O.; Abo-Elenien, O. M. Synthesis of isotactic polypropylene containing a terminal reactive group via metallocene-mediated polymerization/chain transfer reaction in the presence of protected allylamine. Macromol. Ind. J. 2009, 5, 40−52. (33) Cope, A. C. The Precipitation of Phenylmagnesium Bromide by Pyridine and by Dioxane. J. Am. Chem. Soc. 1938, 60, 2215−2217. (34) Saheki, Y.; Sasada, K.; Satoh, N.; Kawaichi, N.; Negoro, K. A Convenient Preparation of Pure Dialkylmagnesium from a Grignard Reagent. Chem. Lett. 1987, 16, 2299−2300. (35) Cope, A. C. The Preparation of Dialkylmagnesium Compounds from Grignard Reagents. J. Am. Chem. Soc. 1935, 57, 2238−2240. (36) Noller, C. R.; White, W. R. The Composition of Grignard Reagents as Determined by Precipitation with Dioxane. J. Am. Chem. Soc. 1937, 59, 1354−1356. (37) Wurtz, A. Sur une nouvelle classe de radicaux organiques. Ann. Chim. Phys. 1855, 44, 275. (38) Hoye, T. R.; Eklov, B. M.; Voloshin, M. No-D NMR Spectroscopy as a Convenient Method for Titering Organolithium (RLi), RMgX, and LDA Solutions. Org. Lett. 2004, 6, 2567−2570.

(3) Sita, L. R. Ex Uno Plures (“Out of One, Many”): New Paradigms for Expanding the Range of Polyolefins through Reversible Group Transfers. Angew. Chem., Int. Ed. 2009, 48, 2464−2472. (4) Samsel, E. G. Preparation of higher aluminum alkyls catalyzed by a chain growth process reaction. EP539876A2, 1993. (5) Gibson, V. C. Shuttling Polyolefins to a New Materials Dimension. Science 2006, 312, 703−704. (6) Valente, A.; Mortreux, A.; Visseaux, M.; Zinck, P. Coordinative Chain Transfer Polymerization. Chem. Rev. 2013, 113, 3836−3857. (7) Kempe, R. How to Polymerize Ethylene in a Highly Controlled Fashion? Chem. - Eur. J. 2007, 13, 2764−2773. (8) Ribeiro, R.; Ruivo, R.; Nsiri, H.; Norsic, S.; D’Agosto, F.; Perrin, L.; Boisson, C. Deciphering the Mechanism of Coordinative Chain Transfer Polymerization of Ethylene Using Neodymocene Catalysts and Dialkylmagnesium. ACS Catal. 2016, 6, 851−860. (9) D’Agosto, F.; Boisson, C. A RAFT Analogue Olefin Polymerization Technique Using Coordination Chemistry. Aust. J. Chem. 2010, 63, 1155−1158. (10) Pelletier, J.-F.; Mortreux, A.; Olonde, X.; Bujadoux, K. Synthesis of new dialkylmagnesium compounds by living transfer ethylene oligoand polymerization with lanthanocene catalyst. Angew. Chem., Int. Ed. Engl. 1996, 35, 1854−1856. (11) Mazzolini, J.; Espinosa, E.; D’Agosto, F.; Boisson, C. Catalyzed chain growth (CCG) on a main group metal: an efficient tool to functionalize polyethylene. Polym. Chem. 2010, 1, 793−800. (12) Lopez, R. G.; Boisson, C.; D’Agosto, F.; Spitz, R.; Boisson, F.; Bertin, D.; Tordo, P. Synthesis and characterization of macroalkoxyamines based on polyethylene. Macromolecules 2004, 37, 3540−3542. (13) Lopez, R. G.; Boisson, C.; D’Agosto, F.; Spitz, R.; Boisson, F.; Gigmes, D.; Bertin, D. E. New functional polyolefins: Towards a bridge between catalytic and RAFT polymerizations? Macromol. Rapid Commun. 2006, 27, 173−181. (14) Lopez, R. G.; Boisson, C.; D’Agosto, F.; Spitz, R.; Boisson, F.; Gigmes, D.; Bertin, D. Catalyzed chain growth of polyethylene on magnesium for the synthesis of macroalkoxyamines: Application to the production of block copolymers using controlled radical polymerization. J. Polym. Sci., Part A: Polym. Chem. 2007, 45, 2705−2718. (15) Mazzolini, J.; Mokthari, I.; Briquel, R.; Boyron, O.; Delolme, F.; Monteil, V.; Bertin, D.; Gigmes, D.; D’Agosto, F.; Boisson, C. ThiolEnd-Functionalized Polyethylenes. Macromolecules 2010, 43, 7495− 7503. (16) Espinosa, E.; Glassner, M.; Boisson, C.; Barner-Kowollik, C.; D’Agosto, F. Synthesis of Cyclopentadienyl Capped Polyethylene and Subsequent Block Copolymer Formation Via Hetero Diels-Alder (HDA) Chemistry. Macromol. Rapid Commun. 2011, 32, 1447−1453. (17) Mazzolini, J.; Boyron, O.; Monteil, V.; Gigmes, D.; Bertin, D.; D’Agosto, F.; Boisson, C. Polyethylene End Functionalization Using Radical-Mediated Thiol-Ene Chemistry: Use of Polyethylenes Containing Alkene End Functionality. Macromolecules 2011, 44, 3381−3387. (18) Unterlass, M. M.; Espinosa, E.; Boisson, F.; D’Agosto, F.; Boisson, C.; Ariga, K.; Khalakhan, I.; Charvet, R.; Hill, J. P. Polyethylenes bearing a terminal porphyrin group. Chem. Commun. 2011, 47, 7057−7059. (19) Mazzolini, J.; Boyron, O.; Monteil, V.; D’Agosto, F.; Boisson, C.; Sanders, G. C.; Heuts, J. P. A.; Duchateau, R.; Gigmes, D.; Bertin, D. Polyethylene end functionalization using thia-Michael addition chemistry. Polym. Chem. 2012, 3, 2383−2392. (20) Briquel, R.; Mazzolini, J.; Le Bris, T.; Boyron, O.; Boisson, F.; Delolme, F.; D’Agosto, F.; Boisson, C.; Spitz, R. Polyethylene Building Blocks by Catalyzed Chain Growth and Efficient End Functionalization Strategies, Including Click Chemistry. Angew. Chem., Int. Ed. 2008, 47, 9311−9313. (21) Bieligmeyer, M.; Taheri, S. M.; German, I.; Boisson, C.; Probst, C.; Milius, W.; Altstaedt, V.; Breu, J.; Schmidt, H.-W.; D’Agosto, F.; Förster, S. Completely Miscible Polyethylene Nanocomposites. J. Am. Chem. Soc. 2012, 134, 18157−18160. F


Amino End-Functionalized Polyethylenes and Corresponding

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