Optimization of the curing conditions of PVC plastisols based on the use of an epoxidized fatty acid ester plasticizer

Effective, Environmentally Friendly PVC Plasticizers Based on Succinic Acid

The plasticizers used in this study were synthesized from renewable raw materials using succinic acid, oleic acid, and propylene glycol. Four environmentally friendly plasticizer samples were obtained; their chemical structures and compositions were confirmed by gas chromatography (GC) and infrared spectroscopy (FT–IR) analyses, and their physicochemical properties and thermal stability (TGA analysis) were investigated. The obtained ester mixtures were used as poly(vinyl chloride) (PVC) plasticizers and their plasticization efficiency was determined in comparison to traditional, commercially available phthalate plasticizers, such as DEHP (di(2-ethylhexyl phthalate) and DINP (diisononyl phthalate). Mechanical properties and migration resistance were determined for soft PVC with the use of three concentrations of plasticizers (40 PHR, 50 PHR, and 60 PHR). It was observed that the obtained plasticizers exhibited the same plasticization efficiency and were characterized with good mechanical and physical properties in comparison to commercial plasticizers. The tensile strength was approx. 19 MPa, while the elongation at break was approx. 250% for all tested plasticizers at a concentration of 50 PHR. Furthermore, plasticizer migration studies showed that the synthesized plasticizers had excellent resistance to plasticizer leaching. The best migration test result obtained was 70% lower than that for DEHP or DINP. The ester mixture that was found to be the most favorable plasticizer was characterized by good thermal and thermo-oxidative stability (5% weight loss temperature: 227.8 °C in air and 261.1 °C in nitrogen). The results of the research clearly indicate that the synthesized esters can provide a green alternative to toxic phthalate plasticizers.

Effective Epoxidation of Fatty Acid Methyl Esters with Hydrogen Peroxide by the Catalytic System H3PW12O40/Quaternary Phosphonium Salts

Six quaternary phosphonium salts (QPSs) in combination with phosphotungstic heteropolyacid, H3PW12O40, were tested in the epoxidation of rapeseed oil fatty acid methyl esters with a hydrogen peroxide aqueous solution. The QPSs consisted of trihexyl(tetradecyl)phosphonium [P6], tributyl-tetradecylphosphonium [P4] or tetraoctylphosphonium [P8] cation and different anions—chloride (Cl−), bromide (Br−), tetrafluoroborate (BF4−), bis(trifluoromethylsulfonyl)amide (NTf2−), bis(2,4,4-trimethyl-pentyl)phosphinate (Phosf−). The influence of the kind of QPS and temperature on the epoxy number, iodine number, glycol content has been determined. The epoxidation was confirmed using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) and elemental analysis CHO. Two QPSs with a trihexyltetradecyphosphonium cation—[P6][Fosf] and [P6][Cl]—were selected as the most effective in the studied epoxidation process. The proposed kinetic model takes into consideration the two reactions, namely, epoxidation and epoxy ring opening involving the formation of hydroxyl groups. The rate constants and activation energies for epoxidation fatty acid methyl esters were determined.

Bio-plastic Films Production from Feather Waste Degradation by Keratinolytic Bacteria Bacillus cereus

Plastic materials have become a necessity of human life especially in the packaging of food commodities and biomedical procedures. Bioplastic is emerging as an effective alternative to fossil oil-based materials to avoid the environmental hazards of the plastic industry. During this study, chicken feathers were used as a substrate to isolate keratin degrading bacteria. Among 14 identified isolates, Bacillus sp BAM3 was found to be the most promising isolate. Partial 16S rDNA analysis-based molecular characterization revealed it is a strain of Bacillus cereus. Bacillus sp BAM3 can grow and produce keratinase in feathers containing basal medium as the sole carbon and energy source. The maximum keratinase production (730U/ml) was achieved within 24 h under optimum reaction conditions. The optimized reaction pH and temperature were noted as 9.0 and 50 °C for crude keratinase activity, respectively. The chicken feathers were used as a substrate in 2, 5, and 10 wt% glycerol to synthesize keratin-based bioplastic with keratinolytic bacterium Bacillus cereus BAM3. Bioplastic prepared from keratin with 2% of glycerol was found to possess good mechanical properties. Therefore, the results present a novel keratinolytic isolate of Bacillus cereus BAM3, which may have potential biotechnological applications in keratin hydrolysis processes. The development of keratin-based bioplastics possessing superior crystalline morphology requires further investigations to substitute fossil oil-based materials.

Biobased Epoxies Derived from Myrcene and Plant Oil: Design and Properties of Their Cured Products

Two biobased epoxy resin monomers derived from myrcene and plant oil are synthesized without using petroleum-based bisphenol A. To obtain material with balanced strength and toughness, the two epoxy monomers are cured together in different weight proportions. Properties of cured epoxy resin are tested by different techniques. Tensile and impact tests indicate that when the content of myrcene-based epoxy is 50-75 wt %, the cured sample has a high strain of 32.30-161.47%, and a moderate tensile strength of 9.57-15.96 MPa. Dynamic mechanical analysis suggests that the glass transition temperature (T _g) of cured samples increases from 17 to 71 °C with the increasing content of myrcene-based epoxy. Morphology of fracture surface indicates that the cured sample containing plant oil-based epoxy resin shows obvious plastic deformation. The curing kinetics of the two epoxies resin is studied by differential scanning calorimetry. Also, the calculated activation energy is 70.49 kJ/mol for myrcene-based epoxy and 64.02 kJ/mol for poly-fatty acid-derived epoxy resin. The thermogravimetric analysis indicates that the main degradation temperature of all cured samples is above 300 °C. The sustainable biobased epoxy has some potential in preparing flexible epoxy materials and can be used to toughen conventional petroleum-based epoxy.

Effect of Modified Cardanol as Secondary Plasticizer on Thermal and Mechanical Properties of Soft Polyvinyl Chloride

This study represents the first attempt to prepare a novel cardanol-based plasticizer. Modified cardanol (MC, i.e., phosphorylated cardanol) containing nitrogen and phosphoric acid groups was synthesized and then incorporated into polyvinyl chloride (PVC) as the secondary plasticizer for partial substitution of dioctyl phthalate (DOP). The molecular structure of MC was characterized by Fourier transform infrared spectroscopy, ¹H nuclear magnetic resonance (NMR), and ³¹P NMR spectroscopy. The thermal degradation behavior, mechanical performance, and compatibility of MC were also investigated. The substitution of DOP with MC enables PVC blends to have higher thermal stability, tensile strength, and leaching resistance. The tensile strength is increased from 17.7 MPa for DOP/PVC blend (MC-0) to 25.7 MPa for MC/PVC blend (MC-4), and the elongation at break is increased from 256 to 432%, respectively. The microstructure of the tensile fractured surface was studied by scanning electron microscopy. The results show that the addition of MC allows PVC blends to have well-balanced properties of flexibility and strength and excellent migration resistance.

On the Use of Gallic Acid as a Potential Natural Antioxidant and Ultraviolet Light Stabilizer in Cast-Extruded Bio-Based High-Density Polyethylene Films

This study originally explores the use of gallic acid (GA) as a natural additive in bio-based high-density polyethylene (bio-HDPE) formulations. Thus, bio-HDPE was first melt-compounded with two different loadings of GA, namely 0.3 and 0.8 parts per hundred resin (phr) of biopolymer, by twin-screw extrusion and thereafter shaped into films using a cast-roll machine. The resultant bio-HDPE films containing GA were characterized in terms of their mechanical, morphological, and thermal performance as well as ultraviolet (UV) light stability to evaluate their potential application in food packaging. The incorporation of 0.3 and 0.8 phr of GA reduced the mechanical ductility and crystallinity of bio-HDPE, but it positively contributed to delaying the onset oxidation temperature (OOT) by 36.5 °C and nearly 44 °C, respectively. Moreover, the oxidation induction time (OIT) of bio-HDPE, measured at 210 °C, was delayed for up to approximately 56 and 240 min, respectively. Furthermore, the UV light stability of the bio-HDPE films was remarkably improved, remaining stable for an exposure time of 10 h even at the lowest GA content. The addition of the natural antioxidant slightly induced a yellow color in the bio-HDPE films and it also reduced their transparency, although a high contact transparency level was maintained. This property can be desirable in some packaging materials for light protection, especially UV radiation, which causes lipid oxidation in food products. Therefore, GA can successfully improve the thermal resistance and UV light stability of green polyolefins and will potentially promote the use of natural additives for sustainable food packaging applications.

Study of the rheology and foaming processes of poly(vinyl chloride) plastisols with different foaming agents

Poly(vinyl chloride) (PVC) plastisols are widely used in the production of flexible PVC foams. In this study, we investigated the evolution of the complex viscosity of PVC plastisol by dynamic oscillatory tests, the storage modulus of the PVC compound by dynamic mechanical analysis, and the thermal behavior including the decomposition of three chemical blowing agents (CBAs), namely, azodicarbonamide, 4,4′-oxybis(benzenesulfonyl hydrazide), and sodium bicarbonate, by differential scanning calorimetry. Furthermore, the morphology and quality of the foams obtained from the corresponding plastisols were characterized by scanning electron microscopy. The results indicated that the onset decomposition temperature T2(5%) of a CBA in plastisol is the most critical indicator of the foam quality. The temperature difference corresponding to [T2(5%) – Tηmax] was also proved to be another important parameter. When T2(5%) is within the optimum temperature range of a PVC plastisol, the bigger the [T2(5%) – Tηmax] difference, the better the quality of the foams.

Keratin based bioplastic film from chicken feathers and its characterization

Plastics have been one of the highly valued materials and it plays an significant role in human's life such as in food packaging and biomedical applications. Bioplastic materials can gradually work as a substitute for various materials based on fossil oil. The issue like sustainability and environmental challenges which occur due to manufacturing and disposal of synthetic plastics can be conquering by bio-based plastics. Feathers are among the most inexpensive abundant, and renewable protein sources. Feathers disposal to the landfills leads to environmental pollutions and it results into wastage of 90% of protein raw material. Keratin is non-burning hydrophilic, and biodegradable due to which it can be applicable in various ways via chemical processing. Main objective of this research is to synthesis bioplastic using keratin from chicken feathers. Extracted keratin solution mixed with different concentration of glycerol (2 to 10%) to produce plastic films. The mixture was stirred under constant magnetic stirring at 60 °C for 5 h. The mixtures are then poured into aluminum weighing boat and dried in an oven at 60 °C for 24 h. The mechanical properties of the samples were tested and the physic-chemical properties of the bioplastic were studied. According to the results, Scanning Electron Microscopy test showed good compatible morphologies without holes, cavity and edge. The difference in chemical composition was analyzed using Fourier transform infrared spectroscopy (FTIR). The samples were also characterized by thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-Ray diffraction (XRD) to check the thermal and crystallinity properties. Other than that, bioplastic made up from keratin with 2% of glycerol has the best mechanical and thermal properties. According to biodegradability test, all bioplastic produced are proven biodegradable. Therefore, the results showed possible application of the film as an alternative to fossil oil based materials which are harmful to the environment.

Heterogenization of Ketone Catalyst for Epoxidation by Low Pressure Plasma Fluorination of Silica Gel Supports

Low pressure plasma was used for preparing heterogeneous organocatalysts 2-(A)-(C) suitable for dioxirane-mediated epoxidations. Heterogenization was accomplished by adsorption of the methyl perfluoroheptyl ketone (2) on fluorinated supports (A)-(C) deriving from the treatment of commercial C₈-silica gel in low pressure plasma fed with fluorocarbons. Catalyst 2-(C) proved to be the most efficient one, promoting epoxidation of an array of alkenes, including unsaturated fatty esters like methyl oleate (10) and the triglyceride soybean oil (11), with the cheap potassium peroxymonosulfate KHSO₅ (caroate) as a green oxidant. Notably, the perfluorinated matrix gives rise to the activation of caroate, generating singlet oxygen. Materials were characterized by infrared Attenuated Total Reflectance spectroscopy (ATR-FTIR), X-ray Photoelectron Spectroscopy (XPS ) and Emission Scanning Electron Microscope (FESEM).

Effect of the particulate morphology of resin on the gelation process of PVC plastisols

The gelation process of poly(vinyl chloride) (PVC) plastisol is very important to ensure the quality of the product and is affected by the type of resins, plasticizers, and other additives. In this study, the gelation process of the as-prepared PVC plastisol was characterized by measuring the evolution of vibrational viscosity with temperature or time using a vibrational viscometer. Furthermore, the effect of some commercial resins with different particulate morphologies on the gelation process was investigated by synchronously combining scanning election microscopy and laser particle size analyses. The results of this study proved that the particle size distribution and the aggregation degree of the secondary particles of a resin are the key factors affecting the gelation process. For the resin with bimodal particle size distribution, the closer the aggregation of the secondary particles, the slower the gel speed; however, an opposite behavior was observed for the resins with unimodal particle size distribution.

Study on the synthesis of bio-based epoxy curing agent derived from myrcene and castor oil and the properties of the cured products

Two biobased curing agents derived from castor oil and myrcene were prepared and were used to cure epoxy E-51.

Liquid phase oxidation chemistry in continuous-flow microreactors

This review gives an exhaustive overview of the engineering principles, safety aspects and chemistry associated with liquid phase oxidation in continuous-flow microreactors.

A novel biobased plasticizer of epoxidized cardanol glycidyl ether: synthesis and application in soft poly(vinyl chloride) films

A novel plasticizer derived from cardanol, and epoxied cardanol glycidyl ether (ECGE), was synthesized and characterized by ¹H-NMR and ¹³C-NMR.

Epoxidized vegetable oils plasticized poly(lactic acid) biocomposites: mechanical, thermal and morphology properties

Plasticized poly(lactic acid) PLA with epoxidized vegetable oils (EVO) were prepared using a melt blending method to improve the ductility of PLA. The plasticization of the PLA with EVO lowers the T_g as well as cold-crystallization temperature. The tensile properties demonstrated that the addition of EVO to PLA led to an increase of elongation at break, but a decrease of tensile modulus. Plasticized PLA showed improvement in the elongation at break by 2058% and 4060% with the addition of 5 wt % epoxidized palm oil (EPO) and mixture of epoxidized palm oil and soybean oil (EPSO), respectively. An increase in the tensile strength was also observed in the plasticized PLA with 1 wt % EPO and EPSO. The use of EVO increases the mobility of the polymeric chains, thereby improving the flexibility and plastic deformation of PLA. The SEM micrograph of the plasticized PLA showed good compatible morphologies without voids resulting from good interfacial adhesion between PLA and EVO. Based on the results of this study, EVO may be used as an environmentally friendly plasticizer that can improve the overall properties of PLA.

Epoxidized Esters of Palm Kernel Oil as an Effective Plasticizer for PVC: A Study of Mechanical Properties and Effect of Processing Conditions

One of the most commonly used vegetable oil plasticizer in polyvinyl chloride (PVC) is epoxidized soybean oil (ESBO). On the contrary, epoxidized palm oil is among the least used, because of its low compatibility with PVC. This work reports that epoxidized and esterified palm kernel oil (EEPKO) has the potential to be used as a plasticizer for PVC. In this study, it was found that a maximum of 65 phr of EEPKO could be incorporated within the PVC resin. In addition, subjecting this EEPKO plasticized PVC (p-PVC) at a processing temperature of 200 °C resulted in much reduced plasticizer loss. EEPKO lowers the glass transition temperature of PVC from 79 °C to −23 °C. The optimum mechanical properties, namely tensile strength, elongation at break and hardness, were obtained for p-PVC processed at 200 °C.

Mechanical, thermal and morphological properties of poly(lactic acid)/epoxidized palm olein blend

Poly(lactic acid) (PLA) is known to be a useful material in substituting the conventional petroleum-based polymer used in packaging, due to its biodegradability and high mechanical strength. Despite the excellent properties of PLA, low flexibility has limited the application of this material. Thus, epoxidized palm olein (EPO) was incorporated into PLA at different loadings (1, 2, 3, 4 and 5 wt%) through the melt blending technique and the product was characterized. The addition of EPO resulted in a decrease in glass transition temperature and an increase of elongation-at-break, which indicates an increase in the PLA chain mobility. PLA/EPO blends also exhibited higher thermal stability than neat PLA. Further, the PLA/1 wt% EPO blend showed enhancement in the tensile, flexural and impact properties. This is due to improved interaction in the blend producing good compatible morphologies, which can be revealed by Scanning Electron Microscopy (SEM) analysis. Therefore, PLA can be efficiently plasticized by EPO and the feasibility of its use as flexible film for food packaging should be considered.

Graphene nanoplatelets as novel reinforcement filler in poly(lactic acid)/epoxidized palm oil green nanocomposites: mechanical properties

Graphene nanoplatelet (xGnP) was investigated as a novel reinforcement filler in mechanical properties for poly(lactic acid) (PLA)/epoxidized palm oil (EPO) blend. PLA/EPO/xGnP green nanocomposites were successfully prepared by melt blending method. PLA/EPO reinforced with xGnP resulted in an increase of up to 26.5% and 60.6% in the tensile strength and elongation at break of the nanocomposites respectively, compared to PLA/EPO blend. XRD pattern showed the presence of peak around 26.5° in PLA/EPO nanocomposites which corresponds to characteristic peak of graphene nanoplatelets. However, incorporation of xGnP has no effect on the flexural strength and modulus. Impact strength of PLA/5 wt% EPO improved by 73.6% with the presence of 0.5 wt% xGnP loading. Mechanical properties of PLA were greatly improved by the addition of a small amount of graphene nanoplatelets (<1 wt%).

A comparative study on the mechanical, thermal and morphological characterization of poly(lactic acid)/epoxidized Palm Oil blend

In this work, poly(lactic acid) (PLA) a fully biodegradable thermoplastic polymer matrix was melt blended with three different epoxidized palm oil (EPO). The aim of this research was to enhance the flexibility, mechanical and thermal properties of PLA. The blends were prepared at various EPO contents of 1, 2, 3, 4 and 5 wt% and characterized. The SEM analysis evidenced successful modification on the neat PLA brittle morphology. Tensile tests indicate that the addition of 1 wt% EPO is sufficient to improve the strength and flexibility compared to neat PLA. Additionally, the flexural and impact properties were also enhanced. Further, DSC analysis showed that the addition of EPO results in a decrease in T_g, which implies an increase in the PLA chain mobility. In the presence of 1 wt% EPO, TGA results revealed significant increase in the thermal stability by 27%. Among the three EPOs used, EPO(3) showed the best mechanical and thermal properties compared to the other EPO’s, with an optimum loading of 1 wt%. Conclusively, EPO showed a promising outcome to overcome the brittleness and improve the overall properties of neat PLA, thus can be considered as a potential plasticizer.

Transfer of the epoxidation of soybean oil from batch to flow chemistry guided by cost and environmental issues

The simple transfer of established chemical production processes from batch to flow chemistry does not automatically result in more sustainable ones. Detailed process understanding and the motivation to scrutinize known process conditions are necessary factors for success. Although the focus is usually "only" on intensifying transport phenomena to operate under intrinsic kinetics, there is also a large intensification potential in chemistry under harsh conditions and in the specific design of flow processes. Such an understanding and proposed processes are required at an early stage of process design because decisions on the best-suited tools and parameters required to convert green engineering concepts into practice-typically with little chance of substantial changes later-are made during this period. Herein, we present a holistic and interdisciplinary process design approach that combines the concept of novel process windows with process modeling, simulation, and simplified cost and lifecycle assessment for the deliberate development of a cost-competitive and environmentally sustainable alternative to an existing production process for epoxidized soybean oil.