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Polyester matrices : role of clays and organo-modification Biodegradable Aliphatic Polyesters Biodegradable polymers with controllable life-time Via enzymatic/hydrolytic chain cleavage and ultimate bioassimilation Biocompatible and bioresorbable materials O (C H 2 ) 5 C O n PCL Industrial production of PCL by Solvay, Dow (Union Carbide), Daicel,… Miscible with numerous commercial thermoplastics… e.g., PVC, SAN, ABS, CPE, nitrocellulose, polycarbonate, (PE),… Poly(ε-caprolactone) : Nanocomposites : organic-inorganic materials First : to improve properties of PCL : stiffness, gas barrier, thermal behavior,… Second : to use highly filled PCL/clay nanocompositions as «&masterbatch&» in various thermoplastic matrices, i.e., PCL behaves as a clay-surface compatibilizer ! "#$$%& "ε!& nanometer scale dispersion O (C H 2 ) 5 C O n PCL Two main methods for PCL nanocomposite synthesis !' ( poly(caprolactone) + clay mixing in the molten state ring-opening polymerization ε-caprolactone + clay + catalyst Clay = Montmorillonite Na x (Al 4-x Mg x )Si 8 O 20 (OH) 4 [CEC = 80-100 mequ./100 g] from Southern Clay Products or Süd Chemie commercial PCL Mn = 50,000 g.mol -1 Montmorillonite (modified) 3 wt% melt blending on a two-roll mill at 130°C for 10 minutes + Poly(ε-caprolactone) nanocomposites by melt intercalation basal spacing (d, Å) in code Ammonium cation (organic fraction wt %) a clay PCL composite b Mont-Na Na + (-) 12.1 12.3 Mont-COOH HOOC-C 11 H 22 NH 3 + (11.2) 13.8 13.7 Mont-C 18 C 18 H 37 NH 3 + (14.1) 18.7 25.6 Mont-Alk (CH 3 ) 2 N + (C 18 H 37 ) 2 (28.9) ca. 29.0 (broad) 36.0 Mont-(OH) 2 (CH 3 )(C 18 H 35 )N + (CH 2 CH 2 OH) 2 (20.1) 18.4 31.0 microcomposite Intercalated nanocomposite a)&determined by TGA b) PCL composite filled with $!% of layered silicates (precluding the organic layer) Pantoustier et al., e-Polymer, 9 (2001) T.E.M. of melt intercalated nanocomposites 200 nm Mont-C 18 Mont-Alk Mont-(OH) 2 C 18 H 37 NH 3 + (C 18 H 37 ) 2 N + (CH 3 ) 2 (C 18 H 35 )(CH 3 )N + (CH 2 CH 2 OH) 2 Exfoliation of the silicate sheets in PCL never complete, it remains some stacks of silicate layers whatever the alkylammonium cations considered semi-intercalated/semi-exfoliated structure ~50nm (Nanofil 848) (Nanofil 15) (Cloisite 30B) Effect of clay content on elastic modulus 150 200 250 300 350 400 450 0 2 4 6 8 10 clay content (w t%) Young modulus (MPa) M MT-Na M MT-Alk M MT-(OH)2 microcomposite nanocomposites Tensile tests with a constant deformation rate : 50 mm/min (638 type V ASTM norm) Pantoustier et al., e-Polymer, 9 (2001) )*+% Effect of (organo)clay? Intercalation/exfoliation? - clay (montmorillonite) 1 to 10 wt-% - slurry in ε-caprolactone (in bulk : no solvent) Activation : Sn or Al-based catalyst O O Sn or Al Catalyst O (CH 2 ) 5 O n n Poly(ε-caprolactone) nanocomposites by in situ polymerization Pantoustier et al, Polym. Eng. Sci., 42 (2002) In-situ polymerization [monomer]/[Sn(Oct) 2 ] = 300 3 wt-% clay analysis by X-ray diffraction Montmorillonite N + CH 3 CH 3 C 8 H 17 C 18 H 37 intercalation d = 18.5 Å Montmorillonite Na + intercalation d = 12 Å d = 19 Å d = 27 Å Montmorillonite N + CH 3 OH OH C 18 H 37 exfoliation d = 20 Å no peak Pantoustier et al, Polym. Eng. Sci., 42 (2002) 100 nm 100 nm Complete exfoliation ,!' (catalysis by ' - ".& - T.E.M. 0 5 10 15 20 25 30 2 theta counts 1 wt% 3 wt% 5 wt% 10 wt% MMT-(CH 2 CH 2 OH) 2 3.25 Å 3.74 Å 4.14 Å XRD N + C 18 H 37 CH 3 OH OH Mont-(OH) 2 Lepoittevin et al., Macromolecules, 35 (2002) [...]... co-intercalation (in H2O at 85°C) of hydroxy-functionalized and non functionalized ammonium cations : CH3 CH2CH2 OH N C18H37 Na+ N C18H37 I- CH3 N C18H37 CH3 1.90 nm CH2 CH2 OH CH3 C18H37 N CH3 ~ 1.9nm CH3 Mont-OH with 100% OH 20 00 count s CH3 with 0, 25 , 50, 75 and 100% intercalated ω-OH ammonium cations (ca 21 ~wt-% organic modifier) CH3 3000 25 00 CH3 CH3 Na+ 1 .21 nm I- 1500 1000 500 0 0 5 10 15 2- theta 20 25 30 Lepoittevin... 0 0 5 10 15 2- theta 20 25 30 Lepoittevin et al., J Mater Chem., 12 (20 02) PCL-« grafted » clay nanohybrids : grafting density control 3 wt-% Mont-OH(x%) Intercalation 8000 0% OH counts 6000 25 % OH 4000 50% OH 75% OH 20 00 100%OH 0 0 5 10 15 20 25 30 2- theta Exfoliation Lepoittevin et al., J Mater Chem., 12 (20 02) PCL-« grafted » clay nanohybrids : grafting density control 3 wt-% Mont-OH(100%) ~ 300nm... PCL Cloisite30B 120 0 cut ( on a ) s u 1000 800 a) 600 b) 400 20 0 c) 0 0 2 4 6 8 10 12 14 2 theta angle (°) Pollet et al., Macromol Chem Phys., 20 04 PCL nanocomposite « masterbatch » by in-situ polymerization masterbatch O O O O O O Mont-(OH )2 O O O O PCL, PVC, PECl,… O O O O Catalyzed ROP O O (C H 2 ) 5 C O O (C H 2 ) 5 C Melt blending n n Masterbatch Highly filled PCL Exfoliated nanocomposites Lepoittevin... process Intercalation 3.88 nm 1.85 nm MMT-(OH) 2 PVC + MMT-(OH) 2 PVC + masterbatch M3 (50% clay/50%PCL) 0 2 4 6 8 10 2- theta Exfoliation (Melt blending at 155°C for 15 min.) Lepoittevin et al., Polymer, 44 (20 03) CPE / (PCL-grafted) Mont(OH )2 nanocomposites via « masterbatch » process With MMT-OH2 Via the PCL-grafted MMT masterbatch 500 nm 500 nm 500 nm Nanocomposites based on 3wt% clay dispersed in stabilized... CPE with 36wt% chlorine (Tyrin®36 52) from Dupont Dow Elastomers and stabilized by 4 phr Lankroflex® E2307 (epoxidized soybean oil) masterbatch process : application to PLA nanocomposites 1 1 2 2 Highly filled (53 wt %) Cloisite®30B / PLA nanocomposite Melt blending In situ polymerisation Preformed PLA (commercial matrix) PLA (70% S-lactic acid) Cloisite®30B / PLA nanocomposites with 3 wt% of loading... Lepoittevin et al., Polymer, 44 (20 03) Thermogravimetric analysis of PCL-grafted Mont-(OH )2 exfoliated in PCL via « masterbatch » process : effect of clay content 1 00 PCL 80 weight % 1 w t% 3 w t% 60 5 w t% PCL 50K 10 w t% 40 20 0 25 0 300 350 400 450 500 temperature °C Lepoittevin et al., Polymer, 44 (20 03) Conditions : 20 °C/min under air flow 550 PVC / (PCL-grafted) Mont(OH )2 nanocomposites via « masterbatch... exfoliation with MMT-(OH )2? N HO R HO + N OHHO R N N HO R + N OH HO R HO OH + + N OH HO R R R N + N OH HO N R + (x+y) + OH R O initiator Catalyst R=C18H35 + O O OH OH OH + + O x H O y H O + N R O OH O In-situ polymerization : catalysis by AlEt3 room temperature, 24 h [ROH] = [AlEt3] Mont-(OH )2 C18H37 CH3 + N OH OH Mont-(OH )2 + AlEt3 Mont-(OAlEt2 )2 + C2H6 PCL-« grafted » clay nanohybrids : grafting density... L,L-lactide from activated clay surface - N OH + 1 AlEt3 , toluene C16H33 - N (-C2H6) + - N O + Et Al Et C16H33 - N + C16H33 C16H33 O O 2 CL O - toluene N O + C CH2 5 O n Et Al Et C16H33 - N + C16H33 O O 3 LA O O toluene 4 H3O+ - N O + C16H33 O - N C O CH2 5 O n C CH O m H CH3 + C16H33 Pollet et al., Macromol Chem Phys., 20 04 Nanohybrids by sequential copolymerization of εcaprolactone and L,L-lactide from... Cloisite®30B / PLA nanocomposites with 3 wt% of loading Paul et al., Macromol Chem Phys., 20 05 PLA nanocomposites via masterbatch process Exfoliation of clay platelets Morphology Masterbatch (53 wt% inorganic) Cloisite®30 B Cloisite®30B / PLA nanocomposites with 3 wt% of Biodegradation tests Weight loss of PCL/clay composites films (5x5 cm and 100 µm thick) in natural composting environment The biodegradability... constant weight Conclusions Polymer layered silicate nanocomposites : New family of performant materials - readily accessible by Melt intercalation In situ intercalative polymerization - easily melt processed and shaped - with much improved properties (barrier, thermal, mechanical, rheological, flame retardan Key-example : Biodegradable polyester-based nanocomposites - next generation of thermoplastic materials . PCL composite b Mont-Na Na + (-) 12. 1 12. 3 Mont-COOH HOOC-C 11 H 22 NH 3 + (11 .2) 13.8 13.7 Mont-C 18 C 18 H 37 NH 3 + (14.1) 18.7 25 .6 Mont-Alk (CH 3 ) 2 N + (C 18 H 37 ) 2 (28 .9). e-Polymer, 9 (20 01) T.E.M. of melt intercalated nanocomposites 20 0 nm Mont-C 18 Mont-Alk Mont-(OH) 2 C 18 H 37 NH 3 + (C 18 H 37 ) 2 N + (CH 3 ) 2 (C 18 H 35 )(CH 3 )N + (CH 2 CH 2 OH) 2 Exfoliation. by ' - ".& - T.E.M. 0 5 10 15 20 25 30 2 theta counts 1 wt% 3 wt% 5 wt% 10 wt% MMT-(CH 2 CH 2 OH) 2 3 .25 Å 3.74 Å 4.14 Å XRD N + C 18 H 37 CH 3 OH OH Mont-(OH) 2 Lepoittevin