CARBON NANOTUBE-GRAFT-BLOCK COPOLYMERS CONTAINING SILVER NANOPARTICLES

Abstract

Polycaprolactone-polylactide block copolymers (PCL-block-PLA) were grafted onto filled multi-wall carbon nanotubes (MWCNT) successfully. In this synthesis, MWCNTs were opened and functionalized, and then they were filled by silver nanoparticles. The filled MWCNT were used as macroinitiator for ring opening polymerization of ε-caprolactone and L-lactide. Then the end hydroxyl functional groups of MWCNT-graft-PCL or MWCNT-graft-PLA were used as initiator for ring opening polymerization of lactide and ε-caprolactone and MWCNT-graft-PCL-block-PLA or MWCNT-graft-PLA-block-PCL were obtained, respectively. Length of grafted copolymer chains onto the MWCNT was controlled using CNT/monomer ratio. Nanocomposites' properties depend on the length of polymer blocks strongly. Structure of nanocomposites was evaluated by TEM and spectroscopy methods.

Physical Properties, Crystallization, and Thermal/Hydrolytic Degradation of Poly(L‐lactide)/Nano/Micro‐Diamond Composites

“…Of the additives, carbon‐based nano‐structured fillers such as fullerene,15–18 single‐wall carbon nanotube (SWCNT) 16, 19–21. multi‐wall carbon nanotube (MWCNT),22–29 and graphene 30–39 are intensively investigated to improve mechanical properties 21, 25, 32, 38 and thermal/hydrolytic degradation‐resistance of PLA‐based materials 16, 20, 27, 32, 34, 39, 40 and to manipulate their hydrolytic degradation behavior. The carbon‐based nano‐structured fillers are known to increase the conductivity 16, 19, 24, 26–28, 38, 39 and accelerate the crystallization of PLLA,15–19, 23, 27, 30, 31, 33, 35, 37–39 which will elevate the crystallinity and thereby the thermal stability of PLA‐based materials, in addition to the effects of incorporated high hardness fillers.…”

Modification of Carbon Nanotubes as an Effective Solution for Cancer Therapy

“…Several water-soluble polymers have been covalently and non-covalently attached onto the surface of CNTs to produce modified water-soluble CNT-polymer (Table 1). Depending on the type of conjugated polymer, modified CNTs can be soluble in aqueous or organic solvents, for example, conjugation of polylactide or polycaprolactone onto the surface of CNTs tends to solubilization of CNTs in organic solvents such as chloroform [102,103]. It has been proved that polymers not only raise the functionality, biocompatibility and water solubility of CNT but also are able to change the CNTs conformations dramatically [102][103][104].…”

“…Depending on the type of conjugated polymer, modified CNTs can be soluble in aqueous or organic solvents, for example, conjugation of polylactide or polycaprolactone onto the surface of CNTs tends to solubilization of CNTs in organic solvents such as chloroform [102,103]. It has been proved that polymers not only raise the functionality, biocompatibility and water solubility of CNT but also are able to change the CNTs conformations dramatically [102][103][104]. According to CNTs' polymeric and cationic innate abilities, soluble functionalized carbon nanotubes seem to represent an innovative drug delivery system, since they are capable to penetrate into the cell without altering their morphology [105,106].…”

Carbon nanotubes in cancer therapy: a more precise look at the role of carbon nanotube–polymer interactions

“…For example, conjugation of polylactide or polycaprolactone onto the surface of CNTs leads to solubilization of CNTs in organic solvents such as chloroform. 180,181 In the case of watersolubilization, one of the most studied polymers for improving water solubility and long blood circulation of CNTs through covalent-noncovalent interactions [182][183][184][185][186][187][188][189] is polyethylene glycol (PEG). In some reports, the water-solubility value of CNTs grafted by PEG in water reaches around 5 mg mL À1 .…”