Synthesis, characterization and crystallization of bionanocomposites based on PLLA, PCL and nanocellulose


Autoria(s): Tavernelli, Alice
Contribuinte(s)

Caretti, Daniele

Müller, Alejandro

Data(s)

16/10/2015

31/12/1969

Resumo

In recent years, environmental concerns and the expected shortage in the fossil reserves have increased further development of biomaterials. Among them, poly(lactide) PLA possess some potential properties such as good ability process, excellent tensile strength and stiffness equivalent to some commercial petroleum-based polymers (PP, PS, PET, etc.). This biobased polymer is also biodegradable and biocompatible However, one great disadvantage of commercial PLA is slow crystallization rate, which restricts its use in many fields. Using of nanofillers is viewed as an efficient strategy to overcome this problem. In this thesis, the effect of bionanofillers in neat PLA and in blends of poly (L-lactide)(PLA)/poly(ε-Caprolactone) (PCL) has been investigated. The used nanofillers are: poly(L-lactide-co-ε-caprolactone) and poly(L-lactide-b-ε-caprolactone) grafted on cellulose nanowhiskers and neat cellulose nanowhiskers (CNW). The grafting reaction of poly(L-lactide-co-caprolactone) and poly (L-lactide-b-caprolactone) on the nanocellulose has been performed by the grafting from technique. In this way the polymerization reaction it is directly initiated on the substrate surface. The condition of the reaction were chosen after a temperature and solvent screening. By non-isothermal an isothermal DSC analysis the effect of bionanofillers on PLA and 80/20 PLA/PCL was evaluated. Non-isothermal DSC scans show a nucleating effect of the bionanofillers on PLA. This effect is detectable during PLA crystallization from the glassy state. Cold crystallization temperature is reduced upon the addition of the poly(L-lactide-b-caprolactone) grafted on cellulose nanowhiskers that is most performing bionanofiller in acting as a nucleating agent. On the other hand, DSC isothermal analysis on the overall crystallization rate indicate that cellulose nanowhiskers are best nucleating agents during isothermal crystallization from the melt state. In conclusion, nanofillers have different behavior depending on the processing conditions. However, the efficiency of our nanofillers as nucleating agent was clearly demonstrated in both isothermal as in non-isothermal condition.

Formato

application/pdf

Identificador

http://amslaurea.unibo.it/9317/1/Alice.Tavernelli_tesi.pdf

Tavernelli, Alice (2015) Synthesis, characterization and crystallization of bionanocomposites based on PLLA, PCL and nanocellulose. [Laurea magistrale], Università di Bologna, Corso di Studio in Chimica industriale [LM-DM270] <http://amslaurea.unibo.it/view/cds/CDS0884/>

Relação

http://amslaurea.unibo.it/9317/

Direitos

info:eu-repo/semantics/openAccess

Palavras-Chave #grafted random copolymers grafted block copolymers cellulose nanowhiskers overall crystallization rate isothermal crystallization rate poly(L-lactide) #Chimica industriale [LM-DM270] #cds :: 0884 :: Chimica industriale [LM-DM270] #sessione :: seconda
Tipo

PeerReviewed

info:eu-repo/semantics/masterThesis

Idioma(s)

en

Publicador

Alma Mater Studiorum - Università di Bologna