Characterization of PLA/PBSeT Blends Prepared with Various Hexamethylene Diisocyanate Contents

Abstract

Poly (lactic acid) (PLA) is the most widely available commercial bioplastic that is used in various medical and packaging applications and three-dimensional filaments. However, because neat PLA is brittle, it conventionally has been blended with ductile polymers and plasticizers. In this study, PLA was blended with the high-ductility biopolymer poly (butylene-sebacate–co–terephthalate) (PBSeT), and hexamethylene diisocyanate (HDI) was applied as a crosslinking compatibilizer to increase the miscibility between the two polymers. PLA (80%) and PBSeT (20%) were combined with various HDI contents in the range 0.1–1.0 parts-per-hundred rubber (phr) to prepare blends, and the resulting physical, thermal, and hydrolysis properties were analyzed. Fourier-transform infrared analysis confirmed that –NH–C=OO− bonds had formed between the HDI and the other polymers and that the chemical bonding had influenced the thermal behavior. All the HDI-treated specimens showed tensile strengths and elongations higher than those of the control. In particular, the 0.3-phr-HDI specimen showed the highest elongation (exceeding 150%) and tensile strength. In addition, all the specimens were hydrolyzed under alkaline conditions, and all the HDI-treated specimens degraded faster than the neat PLA one.

Maleic Anhydride-Grafted PLA Preparation and Characteristics of Compatibilized PLA/PBSeT Blend Films

“…The mechanical properties of neat PLA, PBSeT, and their binary blends were previously reported [14,33]. In the case of simple blending without a compatibilizer, the mechanical properties of soft biodegradable polymers are not fully exploited in the blends because of the low miscibility of PLA and other polymers [26,30,34].…”

“…To overcome these drawbacks of PLA, several studies have been conducted to increase ductility via melt blending that employs flexible biodegradable polymers, such as poly(butylene-adipate-co-terephthalate) (PBAT), polycaprolactone (PCL), poly(butylene succinic acid) (PBS), poly(hydroxy alkanoate) (PHA), and poly(butylene-sebacate-coterephthalate) (PBSeT) [10][11][12][13][14]. Unfortunately, poor interfacial separation occurred in blends of PLA with other biodegradable polymers, resulting in immiscible blends and affecting material mechanical properties and modulus [15,16].…”

“…In a previous study, PBSeT block co-polyester synthesized using sebacic acid (Se), dimethyl terephthalate (DMT), and 1,4-butanediol (BDO) showed high flexibility (>800%) [33]. In addition, adding PBSeT with various HDIs was confirmed to enhance the miscibility and the ductility of PLA blend films [14]. However, the presence of HDI in a PLA/PBSeT blend is potentially harmful in food and pharmaceutical packaging applications.…”

Reinforcing a Thermoplastic Starch/Poly(butylene adipate-co-terephthalate) Composite Foam with Polyethylene Glycol under Supercritical Carbon Dioxide

“…There are plenty of applications for PEG, such as lubricants for industrial uses, excipients in pharmaceutical products, dispersants in toothpastes, antifoaming agents in food or industrial processes, binders, etc. Poly(lactic acid) (PLA) is a biodegradable thermoplastic material with excellent optical properties and high tensile strength [ 23 , 24 , 25 ]. Although the rigidity and low ductility of PLA limit its applications, when mixed with PEG, it acts as a plasticizer and has received much attention towards current research [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ].…”

Optimization and Properties of Polylactic Acid (PLA) / Nypa Fruticans Husks (NFH) Biocomposite Films Via Central Composite Design (CCD) Method

“…Moreover, PLA has a glass transition (Tg) temperature ranging between 55 and 65 °C, and it is brittle at room temperature, fracturing via a crazing mechanism [7,8]. Mechanical brittleness of PLA can be modified by using many strategies such as copolymerization, processing manipulation and blending [9][10][11].…”