Structure and Thermal Properties of Cellulose Diacetate-Graft-Poly(lactic Acid) Copolymer

2011 ◽  
Vol 221 ◽  
pp. 85-89 ◽  
Author(s):  
Wen Jian Deng ◽  
Xu Pin Zhuang ◽  
Ke Tian Guan ◽  
Bo Wen Cheng
Keyword(s):  
Lactic Acid ◽  
Thermal Properties ◽  
Chain Structure ◽  
Decomposition Temperature ◽  
Poly Lactic Acid ◽  
Cellulose Diacetate ◽  
Scanning Calorimetry ◽  
Grafted Copolymer ◽  
Acid Copolymer ◽  
Processing Properties

To improve the thermal behavior of cellulose diacetate, cellulose diacetate-graft-poly(lactic acid) copolymers (CDA-g-PLAs) were synthesized by ring-opening polymerization of L-lactide using stannous octoate (Sn(Oct)2) as catalyst. The molecular structure of the copolymer was characterized by FT-IR and 1H-NMR and the thermal properties were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG-DTA). The results showed that the product was grafted copolymer of cellulose diacetate-graft-poly(lactic acid) with different side-chain structure. The thermal processing properties of CDA-g-PLAs are remarkably improved with melting temperature(Tm) about 140°C which lower than that of CDA and decomposition temperature (Td) higher than 260°C.

scholarly journals Improved Weathering Performance of Poly(Lactic Acid) through Carbon Nanotubes Addition: Thermal, Microstructural, and Nanomechanical Analyses

Biomimetics ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 61
Author(s):  
Thevu Vu ◽  
Peyman Nikaeen ◽  
William Chirdon ◽  
Ahmed Khattab ◽  
Dilip Depan
Keyword(s):  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Uv Light ◽  
Degradation Mechanism ◽  
Decomposition Temperature ◽  
Poly Lactic Acid ◽  
Accelerated Weathering ◽  
Degradation Behavior ◽  
Scanning Calorimetry ◽  
Norrish Type

To understand the interrelationship between the microstructure and degradation behavior of poly(lactic acid) (PLA), single-walled carbon nanotubes (CNTs) were introduced into PLA as nucleating agents. The degradation behavior of PLA-CNT nanocomposites was examined under accelerated weathering conditions with exposure to UV light, heat, and moisture. The degradation mechanism proceeded via the Norrish type II mechanism of carbonyl polyester. Differential scanning calorimetry (DSC) studies showed an increase in glass transition temperature, melting temperature, and crystallinity as a result of the degradation. However, pure PLA showed higher degradation as evidenced by increased crystallinity, lower onset decomposition temperature, embrittlement, and a higher number of micro-voids which became broader and deeper during degradation. In the PLA-CNT nanocomposites, CNTs created a tortuous pathway which inhibits the penetration of water molecules deeper into the polymer matrix, making PLA thermally stable by increasing the initial temperature of mass loss. CNTs appear to retard PLA degradation by impeding mass transfer. Our study will facilitate designing environmentally friendly packaging materials that display greater resistance to degradation in the presence of moisture and UV light.

RETRACTED: Fabrication of Poly(Lactic Acid) Nanofibers by Cotton Candy Method

2017 ◽  
Vol 728 ◽  
pp. 193-198
Author(s):  
Rutchaneekorn Wongpajan ◽  
Supaphorn Thumsorn ◽  
Hiroyuki Inoya ◽  
Masayuki Okoshi ◽  
Hiroyuki Hamada
Keyword(s):  
Differential Scanning Calorimetry ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Electron Microscope ◽  
Air Pressure ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Cotton Candy ◽  
Nozzle Temperature ◽  
Scanning Electron

The poly (lactic acid) (PLA) fiber of biodegradable polymer was fabricated by cotton candy method with small nozzle. The air pressure was varied from 0.2-0.5 MPa with nozzle temperature of 210-260°C. The morphology of fiber was determined by scanning electron microscope (SEM). Thermal properties were examined using differential scanning calorimetry (DSC). SEM results suggested that diameters the PLA fiber at temperature 250°C and air pressure of 0.2 MPa were smaller than the fiber at low and high temperature. The sizes of the fibers were lower than 1 μm and the fibers were irregular size. Crystallinity significantly decreased when increasing barrel temperatures while it slightly changed when varied air pressure. The productivity of PLA fibers was around 30-180 g/h depended on controlled the nozzle temperature and the air pressure.

scholarly journals Antistatic and Thermal Properties of Poly(Lactic Acid)/Polypropylene/Carbon Nanotube Nanocomposites

2020 ◽  
Vol 16 (2) ◽  
pp. 57-69
Author(s):  
Wen Shyang Chow ◽  
Yuan Ting Lim
Keyword(s):  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Poly Lactic Acid ◽  
Compression Moulding ◽  
Scanning Calorimetry ◽  
Blend Ratio ◽  
Crystallisation Temperature ◽  
Pp Blends ◽  
Thermal Stability Of

The aim of this study is to investigate the influence of carbon nanotubes (CNT) on the antistatic and thermal properties of poly(lactic acid)/polypropylene/carbon nanotubes (PLA/PP/CNT) nanocomposites. PLA/PP (blend ratio = 60:40) containing CNT (loading 1.0 to 2.5 phr) was melt-compounded followed by compression moulding. The antistatic properties of PLA/PP/CNT nanocomposites achieved at 2.5 phr CNT loading. Thermogravimetric analysis (TGA) results indicated that the thermal stability of PLA/PP/ CNT nanocomposite was higher than PLA/PP blend. Differential Scanning Calorimetry (DSC) results demonstrated that CNT reduced the cold crystallisation temperature of PLA, while increased the crystallisation temperature of PP, which evidenced the nucleatingability of CNT in the PLA/PP blends.

Properties of Poly(lactic acid) (PLA)/Poly(butylene adipate-co-terephthalate) (PBAT) Blends in the Presence of Antioxidant

2012 ◽  
Vol 506 ◽  
pp. 126-129
Author(s):  
P. Pukpanta ◽  
K. Sirisinha
Keyword(s):  
Lactic Acid ◽  
Thermal Properties ◽  
Decomposition Temperature ◽  
Sem Analysis ◽  
Environmental Responsibility ◽  
Poly Lactic Acid ◽  
Elongation At Break ◽  
Continuous Structure ◽  
Blend Composition

Environmental responsibility is increasing in importance to both consumers and industries. Biopolymer like poly (lactic acid); PLA is an interesting polymer to replace existing petroleum-based material. PLA is very rigid but inherently brittle and easily thermal degraded during processing. To improve the toughness of PLA, poly (butylene adipate-co-terephthalate); PBAT is widely used. This study focuses on the properties of PLA/PBAT blends. The effects of blend composition on the morphology and properties of PLA/PBAT blends were investigated. Also, the use of Irganox antioxidant in improving blend properties is reported. The results showed that the morphology and properties of the blends depend strongly on blend composition. SEM analysis revealed a co-continuous structure in the blend with 50% PLA. The co-continuous structure remained after the addition of Irganox antioxidant. The addition of antioxidant led to a significant improvement in tensile and thermal properties of the blend. The elongation at break and decomposition temperature of the 50/50 blend increased markedly after 0.3% Irganox antioxidant was added.

scholarly journals Thermal and Structural Analysis of Epoxidized Jatropha Oil and Alkaline Treated Kenaf Fiber Reinforced Poly(Lactic Acid) Biocomposites

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2604
Author(s):  
Siti Hasnah Kamarudin ◽  
Luqman Chuah Abdullah ◽  
Min Min Aung ◽  
Chantara Thevy Ratnam
Keyword(s):  
Lactic Acid ◽  
Thermal Properties ◽  
Alkaline Treatment ◽  
Poly Lactic Acid ◽  
Jatropha Oil ◽  
Scanning Calorimetry ◽  
Kenaf Fiber ◽  
Chain Mobility ◽  
Naoh Solution ◽  
Thermal Stability Of

New environmentally friendly plasticized poly(lactic acid) (PLA) kenaf biocomposites were obtained through a melt blending process from a combination of epoxidized jatropha oil, a type of nonedible vegetable oil material, and renewable plasticizer. The main objective of this study is to investigate the effect of the incorporation of epoxidized jatropha oil (EJO) as a plasticizer and alkaline treatment of kenaf fiber on the thermal properties of PLA/Kenaf/EJO biocomposites. Kenaf fiber was treated with 6% sodium hydroxide (NaOH) solution for 4 h. The thermal properties of the biocomposites were analyzed using a differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). It must be highlighted that the addition of EJO resulted in a decrease of glass transition temperature which aided PLA chain mobility in the blend as predicted. TGA demonstrated that the presence of treated kenaf fiber together with EJO in the blends reduced the rate of decomposition of PLA and enhanced the thermal stability of the blend. The treatment showed a rougher surface fiber in scanning electron microscopy (SEM) micrographs and had a greater mechanical locking with matrix, and this was further supported with Fourier-transform infrared spectroscopy (FTIR) analysis. Overall, the increasing content of EJO as a plasticizer has improved the thermal properties of PLA/Kenaf/EJO biocomposites.

Poly(Lactic Acid)/Poly(Vinyl Alcohol)/Graphene Nanocomposites

2018 ◽  
Vol 773 ◽  
pp. 10-14 ◽  
Author(s):  
Jalupak Rattanakot ◽  
Pranut Potiyaraj
Keyword(s):  
Lactic Acid ◽  
Thermal Properties ◽  
Vinyl Alcohol ◽  
Testing Machine ◽  
Poly Lactic Acid ◽  
Poly Vinyl Alcohol ◽  
Mechanical And Thermal Properties ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Graphene Nanocomposites

Poly(lactic acid) (PLA) is an interesting material as an environmentally-friendly replacement of petroleum-based polymers. However, some properties need improvements in order to commercially utilized PLA. In this work, graphene is used as a reinforcing filler and poly(vinyl alcohol) is used as a carrier to enhance dispersion of graphene in PLA matrix. The addition of graphene aims at improving the mechanical and thermal properties of PLA. The functional groups of graphene were characterized by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The mechanical property testing was performed using a universal testing machine. The thermal properties were measured through differential scanning calorimetry (DSC). As a result, the Young’s modulus and the thermal properties of PLA composites increased as the amount of graphene in the composites increased due to improved dispersion of graphene in PLA matrix.

Preparation of Poly(Lactic Acid)/Bentonite Clay Bio-Nanocomposite

2014 ◽  
Vol 775-776 ◽  
pp. 233-237 ◽  
Author(s):  
Dayanne Diniz Souza Morais ◽  
Renata Barbosa ◽  
Keila Machado Medeiros ◽  
Edcleide Maria Araújo ◽  
Tomás Jefférson Alves de Mélo
Keyword(s):  
Differential Scanning Calorimetry ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Pharmaceutical Industry ◽  
Bentonite Clay ◽  
Poly Lactic Acid ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Double Peaks

Recent advances in biodegradable polymers have attracted a great interest not only in traditional areas such as biomedical and pharmaceutical industry, but also in packaging applications, articles and injected membranes. The aim of this work was to produce bio-nanocomposites poly (lactic acid) - PLA with bentonite clay. The bio-nanocomposites were produced by melt intercalation with incorporation of 1 to 3 wt% of organoclay. The degree of dispersion of clays in the polymer, and consequently the structure of bio-nanocomposites produced was evaluated by X-ray diffraction (XRD), and the thermal properties were studied by differential scanning calorimetry (DSC). XRD results indicated the formation of intercalated structures. It was observed the appearance of crystalline melting double peaks in bio-nanocomposites PLA.

scholarly journals Amine Responsive Poly(lactic acid) (PLA) and Succinic Anhydride (SAh) Graft-Polymer: Synthesis and Characterization

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1466 ◽  
Author(s):  
Adrián Lopera-Valle ◽  
Anastasia Elias
Keyword(s):  
Differential Scanning Calorimetry ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Infrared Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Succinic Anhydride ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Amidation Reaction ◽  
Graft Polymers

Amines are known to react with succinic anhydride (SAh), which in reactions near room temperature, undergoes a ring opening amidation reaction to form succinamic acid (succinic acid-amine). In this work, we propose to form an amine-responsive polymer by grafting SAh to a poly(lactic acid) (PLA) backbone, such that the PLA can provide chemical and mechanical stability for the functional SAh during the amidation reaction. Grafting is performed in a toluene solution at mass content from 10 wt% to 75 wt% maleic anhydride (MAh) (with respect to PLA and initiator), and films are then cast. The molecular weight and thermal properties of the various grafted polymers are measured by gel permeation chromatography and differential scanning calorimetry, and the chemical modification of these materials is examined using infrared spectroscopy. The efficiency of the grafting reaction is estimated with thermogravimetric analysis. The degree of grafting is determined to range from 5% to 42%; this high degree of grafting is desirable to engineer an amine-responsive material. The response of the graft-polymers to amines is characterized using X-ray photoelectron spectroscopy, infrared spectroscopy, and differential scanning calorimetry. Changes in the chemical and thermal properties of the graft-polymers are observed after exposure to the vapors from a 400 ppm methylamine solution. In contrast to these changes, control samples of neat PLA do not undergo comparable changes in properties upon exposure to methylamine vapor. In addition, the PLA-g-SAh do not undergo changes in structure when exposed to vapors from deionized water without amines. This work presents potential opportunities for the development of real-time amine sensors.

Thermal Properties of Poly(Lactic Acid) Modified Poly(3-Hydroxybutyrate-co-4-Hydroxbutyrate)

2016 ◽  
Vol 852 ◽  
pp. 677-685
Author(s):  
Mei Li ◽  
Zhi Qiang Li ◽  
Wei Shao
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Tensile Tests ◽  
Poly Lactic Acid ◽  
Flow Properties ◽  
Scanning Calorimetry ◽  
Melt Flow Rate ◽  
Elongation At Break ◽  
Good Flow

The thermal properties of poly (lactic acid)[PLA] modified poly (3 –hydroxybutyrate –co-4 -hydroxbutyrate) [P(3HB-co-4HB)], prepared by melt blending with different blending ratios were investigated by differential scanning calorimetry [DSC], thermogravimetry [TGA], melt flow rate [MFR] and tensile test measurements, and scanning electron microscopy [SEM]. The DSC tests showed that the glass transition temperature, Tg, of P(3HB-co-4HB) increased from-7°C to 56°C when mixed with 50% to 67% of PLA. A decrease in crystallization temperature, Tc, of P(3HB-co-4HB) broadened the melting interval. The MFR tests indicated the blends had good flow properties and the variation of the PLA content had little effect on the flow properties. The tensile tests showed that PLA improved the mechanical properties of P(3HB-co-4HB), including the tensile strength and elongation at break. The blends had the best mechanical properties when the percentage of PLA was 64%.

Thermal and Mechanical Properties of Mulch Film from Poly(Lactic Acid)/Expoxidized Natural Rubber Blends Filled with Rutile TiO2 as Fillers

2013 ◽  
Vol 844 ◽  
pp. 65-68
Author(s):  
Pranee Nuinu ◽  
Kittikorn Samosorn ◽  
Kittisak Srilatong ◽  
Siripa Tongbut ◽  
Sayant Saengsuwan
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Thermal Stability ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Natural Rubber ◽  
Decomposition Temperature ◽  
Poly Lactic Acid ◽  
Thermal And Mechanical Properties ◽  
Thermal Stability Of

The aim of this research was to reduce and improve the brittleness and thermal properties of poly lactic acid (PLA), respectively. Epoxidized natural rubber (ENR) was used to enhance the toughness and rutile titanium dioxide (R-TiO2) as filler was also incorporated to improve the thermal properties of the PLA. 10wt% ENR with epoxidation contents of 25 mol% (ENR25) and 50 mol% (ENR50) and various R-TiO2contents (0-10 phr)were compounded with PLA by using a twin-screw extruder at 155-165°C and a rotor speed of 40 rpm. The pellets of blends were then formed a thin film using a cast film extruder machine and cooled down under air flow. Thermal and mechanical properties and morphology of PLA/ENR/R-TiO2thin film were investigated. The crystallinity of PLA was found to increase with addition of ENR. The mechanical properties of thin film showed that the ENR50 enhanced the elongation but reduced the tensile strength of PLA with addition of R-TiO2at 5 and 10 phr, respectively. The TGA indicated that the addition of 10 phr R-TiO2increased in the decomposition temperature at 5% weight loss (Td5%) of PLA/ENR film. Thus the thermal stability of PLA/ENR50 was found to improve with addition of R-TiO2. From morphology study, the ENR50 phase showed a good dispersion in the PLA matrix. In conclusion, the addition of ENR and R-TiO2was found to enhance both toughness and thermal stability of PLA.

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