scholarly journals Analysis, Development, and Scaling-Up of Poly(lactic acid) (PLA) Biocomposites with Hazelnuts Shell Powder (HSP)

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4080
Author(s):  
Laura Aliotta ◽  
Alessandro Vannozzi ◽  
Daniele Bonacchi ◽  
Maria-Beatrice Coltelli ◽  
Andrea Lazzeri
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Interfacial Adhesion ◽  
Scale Up ◽  
Analytical Models ◽  
Poly Lactic Acid ◽  
Residual Moisture ◽  
The Matrix ◽  
Shell Powder

In this work, two different typologies of hazelnuts shell powders (HSPs) having different granulometric distributions were melt-compounded into poly(lactic acid) (PLA) matrix. Different HSPs concentration (from 20 up to 40 wt.%) were investigated with the aim to obtain final biocomposites with a high filler quantity, acceptable mechanical properties, and good melt fluidity in order to be processable. For the best composition, the scale-up in a semi-industrial extruder was then explored. Good results were achieved for the scaled-up composites; in fact, thanks to the extruder venting system, the residual moisture is efficiently removed, guaranteeing to the final composites improved mechanical and melt fluidity properties, when compared to the lab-scaled composites. Analytical models were also adopted to predict the trend of mechanical properties (in particular, tensile strength), also considering the effect of HSPs sizes and the role of the interfacial adhesion between the fillers and the matrix.

scholarly journals Mechanical Properties and Bioactivity of Poly(Lactic Acid) Composites Containing Poly(Glycolic Acid) Fiber and Hydroxyapatite Particles

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 249
Author(s):  
Han-Seung Ko ◽  
Sangwoon Lee ◽  
Doyoung Lee ◽  
Jae Young Jho
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Flexural Strength ◽  
Interfacial Adhesion ◽  
Glycolic Acid ◽  
Compact Bone ◽  
Poly Lactic Acid ◽  
Coupling Reactions ◽  
The Poor ◽  
Human Compact Bone

To enhance the mechanical strength and bioactivity of poly(lactic acid) (PLA) to the level that can be used as a material for spinal implants, poly(glycolic acid) (PGA) fibers and hydroxyapatite (HA) were introduced as fillers to PLA composites. To improve the poor interface between HA and PLA, HA was grafted by PLA to form HA-g-PLA through coupling reactions, and mixed with PLA. The size of the HA particles in the PLA matrix was observed to be reduced from several micrometers to sub-micrometer by grafting PLA onto HA. The tensile and flexural strength of PLA/HA-g-PLA composites were increased compared with those of PLA/HA, apparently due to the better dispersion of HA and stronger interfacial adhesion between the HA and PLA matrix. We also examined the effects of the length and frequency of grafted PLA chains on the tensile strength of the composites. By the addition of unidirectionally aligned PGA fibers, the flexural strength of the composites was greatly improved to a level comparable with human compact bone. In the bioactivity tests, the growth of apatite on the surface was fastest and most uniform in the PLA/PGA fiber/HA-g-PLA composite.

Composites of Poly(lactic Acid) with Rice Straw Fibers Modified by Poly(butyl Acrylate)

2011 ◽  
Vol 675-677 ◽  
pp. 357-360
Author(s):  
Li Jun Qin ◽  
Jian Hui Qiu ◽  
Ming Zhu Liu ◽  
Sheng Long Ding ◽  
Liang Shao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Lactic Acid ◽  
Rice Straw ◽  
Butyl Acrylate ◽  
Interfacial Adhesion ◽  
Suspension Polymerization ◽  
Water Solution ◽  
Poly Lactic Acid ◽  
Biodegradable Composites

The modified rice straw fibers (MRSF) were prepared by suspension polymerization technique of butyl acrylate (BA) monomer and rice straw fibers (RSF) in water solution. FTIR test indicated that PBA was coated and absorbed on RSF.The biodegradable composites were prepared with the MRSF and poly(lactic acid) (PLA) by HAAKE rheometer. Mechanical properties showed that the tensile strength of PLA/MRSF composites were (W (%) =7.98%) increased by 6 MPa compared with blank sample. The possible reason was that the good interfacial adhesion between PLA and MRSF, which was demonstrated by SEM.

PLA-Based Biodegradable Copolyester Nanocomposites: Preparation, Characterization and Mechanical Properties

2011 ◽  
Vol 380 ◽  
pp. 290-293
Author(s):  
Bing Tao Wang ◽  
Ping Zhang ◽  
De Gao
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Lactic Acid ◽  
Interfacial Adhesion ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Elongation At Break ◽  
Butylene Terephthalate ◽  
The Matrix ◽  
Different Characteristics

In situ melt copolycondensation was proposed to prepare biodegradable copolyester nanocomposites based on degradable components poly(L-lactic acid) (PLA), rigid segments poly(butylene terephthalate) (PBT), and nanoparticles polyhedral oligomeric silsesquioxanes (POSS). The morphologies and dispersions of two POSS nanoparticles (POSS-NH2 and POSS-PEG) in the copolyester PLABT matrix and their effects on the mechanical properties were investigated. The results demonstrated that the morphologies and dispersions of POSS-NH2 and POSS-PEG showed quite different characteristics. POSS-PEG took better dispersion in the PLABT, while POSS-NH2 had poor dispersions and formed crystalline microaggregates. Due to the good dispersion and strong interfacial adhesion of POSS-PEG with the matrix, the tensile strength and Young’s modulus were greatly improved from 6.4 and 9.6 MPa for neat PLABT up to 11.2 and 70.7 MPa for PLABT/POSS-PEG nanocomposite. Moreover, the incorporation of POSS-PEG could impart macromolecular chains good flexibility and improve the mobility of the chains, so the the elongation at break of PLABT/POSS-PEG nanocomposite dramatically increased from 190 to 350 % compared with neat PLABT.

scholarly journals Barrier Properties and Hydrophobicity of Biodegradable Poly(lactic acid) Composites Reinforced with Recycled Chinese Spirits Distiller’s Grains

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2861
Author(s):  
Zhi-Jun Chen ◽  
Chi-Hui Tsou ◽  
Meng-Lin Tsai ◽  
Jipeng Guo ◽  
Manuel Reyes De Guzman ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Barrier Properties ◽  
Poly Lactic Acid ◽  
Control Group ◽  
Scanning Calorimetry ◽  
Melt Mixing ◽  
Distiller's Grains ◽  
The Matrix ◽  
Section Structure

Adding natural biomass to poly(lactic acid) (PLA) as a reinforcing filler is a way to change the properties of PLA. This paper is about preparing PLA/biomass composites by physically melting and blending Chinese Spirits distiller’s grains (CSDG) biomass and PLA to optimize the composite performance. Composites of modified PLA (MPLA) with varying amounts of CSDG were also prepared by the melt-mixing method, and unmodified PLA/CSDG composites were used as a control group for comparative analysis. The functional groups of MPLA enhanced the compatibility between the polymer substrate and CSDG. The composite water vapor/oxygen barrier and mechanical properties were studied. It was found that the barrier and mechanical properties of MPLA/CSDG composites were significantly improved. SEM was adopted to examine the tensile section structure of the composites, and the compatibility between the filler and the matrix was analyzed. An appropriate amount of CSDG had a better dispersibility in the matrix, and it further improved the interfacial bonding force, which in turn improved the composite mechanical properties. X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry were conducted to determine the crystalline properties and to analyze the stability of the composites. It was found that the CSDG content had a significant effect on the crystallinity. Barrier and biodegradation mechanisms were also discussed.

Poly(lactic acid)/polypropylene and compatibilized poly(lactic acid)/polypropylene blends prepared by a vane extruder: analysis of the mechanical properties, morphology and thermal behavior

2015 ◽  
Vol 35 (8) ◽  
pp. 753-764 ◽  
Author(s):  
Rong-yuan Chen ◽  
Wei Zou ◽  
Hai-chen Zhang ◽  
Gui-zhen Zhang ◽  
Zhi-tao Yang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Thermal Resistance ◽  
Flexural Modulus ◽  
Weight Fraction ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Crystallization Property ◽  
The Matrix ◽  
Pp Blends

Abstract Poly(lactic acid) (PLA)/polypropylene (PP) blends with different weight fractions were prepared by a novel vane extruder. The mechanical properties, morphology, crystallization behavior and thermal stability of the blends were investigated. The tensile strength, flexural strength and elongation at break decreased nonlinearly when the PP content was not more than 50 wt% and then increased with an increase in the PP content. The flexural modulus decreased with increasing PP weight fraction. The PLA/PP 90:10 blend exhibited the optimum impact strength. Scanning electron microscopy measurements revealed that the PLA/PP blends were immiscible. Phase separation occurred significantly at a blend ratio of 50:50. Regarding the PLA/PP 90:10 blend, the mean diameter of the disperse-phase PP particles was the smallest at 1.11 μm. Differential scanning calorimetry measurements showed that low content of PP enhanced the crystallization of PLA. The PLA component in the blends impeded the crystallization of PP when PP was used as the matrix. The thermogravimetric analysis measurement involved a two-step decomposition process of the blends. The thermal resistance of the blends was improved by compounding with PP. As compatibilizers, both the maleic anhydride-grafted PP and the ethylene/n-butyl acrylate/glycidyl methacrylate terpolymer helped improve the mechanical properties, crystallization property and thermal resistance of the PLA/PP blends.

The effect of nanoparticles shape on the mechanical properties of poly lactic acid matrix

2021 ◽  
pp. 009524432098816
Author(s):  
Sajjad Daneshpayeh ◽  
Faramarz Ashenai Ghasemi ◽  
Ismail Ghasemi
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Impact Strength ◽  
Tensile Tests ◽  
Poly Lactic Acid ◽  
The Matrix ◽  
Multi Walled Carbon Nanotubes ◽  
Four Levels ◽  
Carbon Fillers ◽  
Walled Carbon Nanotubes

In this research, mechanical properties of poly lactic acid (PLA)-based nanocomposites were investigated. The nanocomposites were fabricated by adding of three types of nano-materials including multi-walled carbon nanotubes (MWCNT), carbon black (CB) nanoparticles and graphene nano-platelets (GnPs) in four levels from 0 to 3 wt.% to PLA matrix by an internal mixer. Tensile and impact tests were performed to obtain the mechanical properties of nanocomposites. Moreover, field-emission scanning electron microscopy (FESEM) was used to observe the state of nano-fillers dispersion. The FESEM images showed that CB nanoparticles and MWCNT are well distributed in the matrix, but that GnPs are agglomerated. The results of the tensile tests showed that the addition of MWCNT and CB nanoparticles increased the tensile strength by 36% and 76% and the elastic modulus by 10% and 68%, respectively. Also, the presence of all three types of carbon fillers at low loading increased the elongation at break of PLA matrix, and this increase was more significant for GnPs by 55% in the 1 wt.% loading. Finally, the PLA polymer become more brittle with the addition of nanotubes and nano-platelets, and its impact strength was reduced. While, the CB nanoparticles increased the absorbing energy and impact strength.

Improving mechanical properties of ramie/poly (lactic acid) composites by synergistic effect of fabric cyclic loading and alkali treatment

2016 ◽  
Vol 47 (3) ◽  
pp. 390-407 ◽  
Author(s):  
Jianxia Yang ◽  
Luping Zhu ◽  
Zhuo Yang ◽  
Lan Yao ◽  
Yiping Qiu
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Lactic Acid ◽  
Cyclic Loading ◽  
Synergistic Effect ◽  
Interfacial Adhesion ◽  
Alkali Treatment ◽  
Flexural Modulus ◽  
Poly Lactic Acid ◽  
Orientation Factor

Natural cellulose fiber reinforced biopolymer composites have attracted increasing attention due to environmental concerns. However, these fibers have relatively low mechanical properties and poor interfacial adhesion with matrices, limiting their composite mechanical properties. This study investigates the synergistic effect of two recently developed techniques to maximize the mechanical performance of ramie/poly (lactic acid) laminated composites, namely alkali treatment to loosen fiber molecular structure and to increase fiber surface roughness and subsequent cyclic loading treatment to fabrics to increase their tensile strength and modulus. The results show that the treated fabrics have increased crystallinity and crystal orientation factor as well as better orientation of fibers and more uniform structures, leading to 11% improvement in fabric tensile strength and 57% enhancement of tensile strength (90.9 MPa), 48% higher tensile modulus (5.6 GPa), 18% higher flexural strength (149.4 MPa), and 91% higher flexural modulus (8.2 GPa) for the corresponding composites. Meanwhile, postmortem analysis shows that better interfacial adhesion is achieved using this approach.

Mechanical Properties of Bamboo Charcoal (BC)/Poly(Lactic) Acid (PLA) Composites

2019 ◽  
Vol 801 ◽  
pp. 121-126
Author(s):  
Rapeeporn Srisuk ◽  
Laongdaw Techawinyutham ◽  
Wantana Koetniyom ◽  
Rapeephun Dangtungee
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Lactic Acid ◽  
Shear Viscosity ◽  
Tensile Modulus ◽  
Poly Lactic Acid ◽  
Bamboo Charcoal ◽  
Elongation At Break ◽  
The Matrix

The influence of bamboo charcoal (BC) in Poly (lactic) acid (PLA) matrix as masterbatch was studied on mechanical 40:60, 50:50 and 60:40 of masterbatch. BC MBs were diluted at 1 phr, 3 phr, and 5 phr. BC showed even distribution in PLA matrix; however,, it decreased compatibility in the matrix. The infusion of BC in PLA matrix enhanced the tensile modulus; however, there was a reduction in the tensile strength and the elongation at break. It could also be ascertained that there is no signification difference in the hardness of BC/PLA composites compared with neat PLA. The addition of BC slightly decreased shear viscosity of the composites. The optimal BC content in the composites was found to be 2.82wt.% (5 phr 60:40).

scholarly journals Evaluation of Mechanical and Interfacial Properties of Bio-Composites Based on Poly(Lactic Acid) with Natural Cellulose Fibers

2019 ◽  
Vol 20 (4) ◽  
pp. 960 ◽  
Author(s):  
Laura Aliotta ◽  
Vito Gigante ◽  
Maria Coltelli ◽  
Patrizia Cinelli ◽  
Andrea Lazzeri
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Agricultural Waste ◽  
Natural Fibers ◽  
Analytical Models ◽  
Poly Lactic Acid ◽  
Polymeric Matrices ◽  
Cellulosic Fibers ◽  
Natural Cellulose ◽  
Wide Range

The circular economy policy and the interest for sustainable material are inducing a constant expansion of the bio-composites market. The opportunity of using natural fibers in bio-based and biodegradable polymeric matrices, derived from industrial and/or agricultural waste, represents a stimulating challenge in the replacement of traditional composites based on fossil sources. The coupling of bioplastics with natural fibers in order to lower costs and promote degradability is one of the primary objectives of research, above all in the packaging and agricultural sectors where large amounts of non-recyclable plastics are generated, inducing a serious problem for plastic disposal and potential accumulation in the environment. Among biopolymers, poly(lactic acid) (PLA) is one of the most used compostable, bio-based polymeric matrices, since it exhibits process ability and mechanical properties compatible with a wide range of applications. In this study, two types of cellulosic fibers were processed with PLA in order to obtain bio-composites with different percentages of microfibers (5%, 10%, 20%). The mechanical properties were evaluated (tensile and impact test), and analytical models were applied in order to estimate the adhesion between matrix and fibers and to predict the material’s stiffness. Understanding these properties is of particular importance in order to be able to tune and project the final characteristics of bio-composites.

Sign in / Sign up

Export Citation Format

Share Document