Dioctyl Phthalate Plasticizer Research Articles

Structural modification of waste cooking oil methyl esters as cleaner plasticizer to substitute toxic dioctyl phthalate

Abstract Most of the plasticizers used during poly (vinyl chloride) processing are typically toxic petroleum-based phthalates. Furthermore, large amount of edible oils become waste all over the world, fortunately, waste cooking oils have the potential to be an economic alternative for synthesizing different biomaterials. This study aimed to synthesis an improved properties and cost competitiveness cleaner bio-plasticizer using waste cooking oil methyl esters as staring raw materials. In this paper, waste cooking oil methyl esters were structurally modified i.e., transesterification and epoxidation reaction, to prepare epoxide waste cooking oil 2-ethylhexyl esters. The in-situ epoxidation was mainly studied by response surface methodology, with optimum conditions: reaction time was 7 h, molar ratio of C C bonds/FA/H2O2 was 1.00/0.35/2.41, and reaction temperature was 65.84 °C with a maximum relative percentage conversion to oxirane of 92%. Also, the plasticizing effectiveness of epoxide waste cooking oil 2-ethylhexyl esters to substitute toxic plasticizer dioctyl phthalate were studied. Results showed that the mechanical and thermal performance of PVC samples was significantly improved with partial substitutions, while the migration resistance was slightly decreased. Comparison with conventional epoxy compound highlighted that epoxide waste cooking oil 2-ethylhexyl esters had superior low temperature property, oxidation stability, and remarkably reduced the glass transition temperature of PVC. In conclusion, the prepared epoxide via structural modification from waste cooking oil methyl esters proved to be an effective alternative to dioctyl phthalate, replacing about 40% of the total plasticizer. This may lead to the eco-development of waste cooking oil materials, and makes the plasticizing process more environmentally friendly.

Synthesis and application of a novel environmental C26 diglycidyl ester plasticizer based on castor oil for poly(vinyl chloride)

A castor oil-derived diglycidyl ester plasticizer (C26-DGE) was prepared and incorporated into poly(vinyl chloride) (PVC) for the first time. The chemical structure of the product was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and carbon-13 nuclear magnetic resonance (13C-NMR). The plasticizing effects of C26-DGE as a primary or secondary plasticizer for the commercial plasticizer dioctyl phthalate (DOP) were studied. The mechanical properties, thermal stability, and migration stabilities of PVC films were investigated using dynamic mechanical analysis, thermogravimetric analysis (TGA), TGA-FTIR analysis, and PVC film surface analysis. Tensile, volatility, and extraction tests were also done. The castor oil-based plasticizer was found to endow the PVC matrix with enhanced compatibility and flexibility. With partially or completely substituted DOP, C26-DGE significantly increased the thermal stability of PVC blends. Furthermore, the volatility and extraction resistance of the novel plasticizers were generally superior to those of DOP. The interaction between the C26-DGE and PVC molecules and the thermal degradation process of PVC blends were also investigated.

Synthesis and application of a novel cardanol‐based plasticizer as secondary or main plasticizer for poly(vinyl chloride)

AbstractA novel plasticizer based on cardanol, hydrogenated cardanol glycidyl ether acetic ester containing phosphaphenanthrene group (HCGEP), was prepared and incorporated into poly(vinyl chloride) (PVC) for the first time. The molecular structure was characterized with Fourier transform infrared and 1H NMR spectroscopies. The thermal degradation behavior and flame retardant performance of PVC films with HCGEP as secondary or main plasticizer were investigated using thermogravimetric analysis, combustion tests, limiting oxygen index tests and morphological analysis of residues. Furthermore, the mechanical properties of PVC films were examined based on the results of tensile testing. The results were compared to those of the petroleum‐based plasticizer dioctyl phthalate. With the substitution of dioctyl phthalate with HCGEP, PVC films exhibited high thermal stability and better flame retardant performance. The tensile test results showed that the addition of HCGEP could endow PVC resin with well‐balanced properties of flexibility, strength and hardness. © 2017 Society of Chemical Industry

Blending Optimization of Non-Dioctyl Phthalate Plasticized Poly (vinyl chloride) Formulations

ABSTRACTThe use of non-ortho-phthalate plasticizers in poly (vinyl chloride) (PVC) packaging materials and medical devices has been in increasing demand due to worldwide regulatory trends to minimize or eliminate phthalate plasticizers (particularly di(2-ethylhexyl)phthalate (DEHP) or dioctyl phthalate (DOP)) in the PVC industry. This study evaluates the dry-blending cycle time of a suspension grade PVC formulated with various non-DOP plasticizers, di-(2-ethylhexyl) terephthalate (DEHT or DOTP), tris (2-ethylhexyl) trimellitate (TEHTM or TOTM) and alkyl sulphonic phenyl ester (ASE), and compares them with the DOP standard. A design of experiments was also conducted to study the critical dry-blending parameters for optimization of PVC formulated with only DEHT. Effects of PVC temperature (measured during plasticizer addition to the blender), plasticizer pre-heat temperature, plasticizer and lubricant concentrations and the method of plasticizer addition on the dry-blending cycle time and peak amperage of the blender were studied. The blending cycle time is shown to be related to the resultant plasticizer efficiency and the peak amperage is related to the power consumption (the energy required to mix the PVC).

Synthesis and Properties of a Novel Environmental Epoxidized Glycidyl Ester of Ricinoleic Acetic Ester Plasticizer for Poly(vinyl chloride).

A novel renewable plasticizer based on castor oil, epoxidized glycidyl ester of ricinoleic acetic ester (EGERAE), was synthesized and applied into Poly(vinyl chloride) (PVC) for the first time. Its molecular structure was characterized by FT-IR and 1H NMR. The effects of replacement of petroleum-based commercial plasticizer dioctyl phthalate (DOP) with EGERAE in poly(vinyl chloride) (PVC) films were researched. Thermal stability, dynamic mechanical property and mechanical properties of PVC films were investigated with thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests. The results indicated that this castor oil-based plasticizer was able to improve the thermal stability of PVC blends when partially of completely substituting for DOP. Furthermore, EGERAE endowed PVC resin with enhanced flexibility. In addition, the exudation, volatility and extraction resistance characteristics of plasticizers were researched. The degradation mechanism and possible interaction between EGERAE and PVC molecules in the plasticized system were also investigated.

Cardanol Groups Grafted on Poly(vinyl chloride)-Synthesis, Performance and Plasticization Mechanism.

Internally plasticized poly(vinyl chloride) (PVC) materials are investigated via grafting of propargyl ether cardanol (PEC). The chemical structure of the materials was studied by FT-IR and 1H NMR. The performace of the obtained internally plasticized PVC materials was also investigated with TGA, DSC and leaching tests. The results showed that grafting of propargyl ether cardanol (PEC) on PVC increased the free volume and distance of PVC chains, which efficiently decreased the glass transition temperature (Tg). No migration was found in the leaching tests for internally plasticized PVC films compared with plasticized PVC materials with commercial plasticizer dioctyl phthalate (DOP). The internal plasticization mechanism was also disscussed according to lubrication theory and free volume theory. This work provides a meaningful strategy for designing no-migration PVC materials by introducing cardanol groups as branched chains.

Volatility of some aromatic nitrosubstituted plasticizers for polymers

Nine derivatives of nitrophthalic acids and nitrophenols were synthesized as potential plasticizers for polymers and structurally characterized by 1H NMR and elemental analysis. The time dependences of the weight loss for the nitro derivatives synthesized and for commercial plasticizers (dibutyl phthalate and dioctyl phthalate) were obtained by gravimetric method at 100oC, and their volatilities and dipole moments were calculated. The resultant nitroplasticizers are considerably less volatile than dibutyl phthalate. Low volatility is associated not so much with high molecular weight as with high polarity. The nitroplasticizers are well compatible with cellulose esters and exhibit low rates of migration from polymer films.

Synthesis and application of environmental soybean oil‐based epoxidized glycidyl ester plasticizer for poly(vinyl chloride)

A novel environmental soybean oil‐based plasticizer, epoxidized glycidyl ester of soybean oil fatty acids (EGESOFa), was synthesized and characterized by Fourier transform infrared (FTIR), 1H‐nuclear magnetic resonance (1H‐NMR), and 13C‐nuclear magnetic resonance (13C‐NMR). Effects of EGESOFa substitution of commercial plasticizer dioctyl phthalate (DOP) in poly(vinyl chloride) (PVC) films were studied. Dynamic mechanical property, thermal stability and mechanical properties of PVC films plasticized with different content of EGESOFa were investigated with dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and tensile and hardness tests. The results indicated that soybean oil‐based plasticizer could significantly increase plasticizing effect and improve thermal stability of PVC blends when partially of completely replaced DOP. Furthermore, EGESOFa could endow PVC resin with well‐balanced properties of flexibility, strength, and hardness. Surface characterization of films and the possible interaction between plasticizers and PVC molecular were also investigated. This soybean oil‐based alternative plasticizer has the potential to be a main or secondary plasticizer in food packing, children toys, medical devices, and other environmental plastic materials.Practical applications: An efficient alternative plasticizer was obtained in this study. The addition of EGESOFa to the PVC blends could be a potential application to manufacture high‐performance PVC products for the markets with high safety, health, and environmental demands, which are currently restricted to the petroleum‐based phthalates. This could be also a new way of soybean oil for industrial uses.A novel soybean oil‐based alternative plasticizer, epoxidized glycidyl ester of soybean oil fatty acids (EGESOFa), is successfully prepared and applied as a main or secondary plasticizer for poly(vinyl chloride).

Effect of the matrix plasticization behavior on mechanical properties of PVC/ABS blends

Abstract Acrylonitrile-butadiene-styrene (ABS) grafted copolymer prepared by emulsion polymerization was used to modify different molecular weight poly (vinyl chloride) (PVC) resins. The effects of the molecular weight of the PVC resins on dynamic mechanical analyses (DMA) of PVC/ABS blends and matrix plasticizing behavior on the impact mechanical properties and the morphology were investigated. The tan δ peaks of PVC/ABS blends occurred at the same temperature obtained by DMA, indicating that miscibility of PVC/ABS blends was independent of the molecular weight of PVC. The notched Izod impact test results indicated that the amount of polybutadiene (PB) rubber needed for the brittle-ductile transition (BDT) increases together with the molecular weight of PVC when milled at 165°C. Increasing the operation temperature and adding the plasticizer dioctyl phthalate (DOP) could change the matrix plasticizing extent and the BDT. At a milling temperature of 165°C, the BDT was reached only with 3.6 wt% PB when DOP was added, in contrast to the addition of 7.2 wt% PB in the absence of DOP. The morphology of different plasticized degree of PVC/ABS blends was studied by transmission electron microscopy (TEM) showing that the PVC-1/ABS blends milled at 165°C showed a larger unstained area than the other series of PVC blends.

Thermal behavior of epoxidized cardanol diethyl phosphate as novel renewable plasticizer for poly(vinyl chloride)

A novel plasticizer, epoxidized cardanol diethyl phosphate (ECEP), based on cardanol was synthesized. Chemical structure of ECEP was characterized by fourier transform infrared (FTIR), 1H -nuclear magnetic resonance(1H NMR) and 13C -nuclear magnetic resonance(13C NMR). Effects of ECEP substitution for the petroleum-based plasticizer dioctyl phthalate (DOP) in soft poly(vinyl chloride) (PVC) films were studied. Thermal stability and mechanical properties before and after aging of PVC films plasticized with different content of ECEP were investigated with thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests. The results indicated that PVC films plasticized with ECEP showed increased thermal stability. When DOP was substituted for ECEP completely, glass transition temperature (Tg) of PVC films decreased from 41.07 °C to 33.20 °C, the 10% and 50% weight loss temperatures (T10 and T50) increased by 31.57 °C and 23.09 °C respectively. The mechanical properties of PVC films before and after aging were also investigated.

Green plasticizers derived from soybean oil for poly(vinyl chloride) as a renewable resource material

Vegetable oil based plasticizers have potential use as nontoxic and sustainable plasticizer and as replacements for commonly used phthalate plasticizers. In this study, novel soybean oil based polyol esters (derived from glycerin or pentaerythritol, of which two were acetylated and two were additionally epoxidized) were synthesized and characterized with GPC, FT-IR and 1H NMR. Properties of poly (vinyl chloride) (PVC) plasticized with different soybean oil based polyol ester as main plasticizer were evaluated and compared to that of traditional plasticizers dioctyl phthalate (DOP) and epoxidized soybean oil (ESO). It has been proved that thermal stability of PVC blends could be improved by soybean oil based polyol ester plasticizers. Plasticizing effect of pentaerythritol derived soybean oil polyesters on PVC is better than that of DOP, ESO, and glycerin derived soybean oil polyesters. Tests of migration stability showed that with the increasing of the molecular weight, branching degree of molecular and ester bands of soybean oil based polyol ester, the migration stability was enhanced. This study may lead to the development of new type of PVC materials using soybean oil based polyol ester as main plasticizer.

Synthesis of a secondary plasticizer for poly(vinyl chloride) by recycling of poly(ethylene terephthalate) bottle waste through aminolytic depolymerization

This study focuses on the synthesis and application of didecanoate of bis(3‐hydroxypropyl) terephthalamide (DD‐BHPTA) as a secondary plasticizer in poly(vinyl chloride) (PVC) compounding. DD‐BHPTA was synthesized from poly(ethylene terephthalate) bottle waste through aminolysis followed by condensation reaction with decanoic acid. Synthesized DD‐BHPTA was characterized by Fourier‐transform infrared spectroscopy, differential scanning calorimetry, and nuclear magnetic resonance. Plasticized PVC was prepared by compounding PVC in different ratios with DD‐BHPTA and dioctyl phthalate (DOP) using a two‐roll mill. This newly synthesized plasticizer completely fused with PVC. The mechanical, thermal, and rheological properties like glass transition temperature, tensile strength, % elongation, dynamic mechanical analysis, solvent resistance, accelerated ultraviolet weathering test for color stability, differential scanning calorimetry, and thermal gravimetric analysis of plasticized PVC were investigated. DD‐BHPTA along with DOP plasticizer demonstrated plasticization efficiency similar to that of DOP alone, with the same plasticizer loading. DD‐BHPTA was found to be the more efficient plasticizer when used in combination with DOP. Thus, DD‐BHPTA can be used as a secondary plasticizer for DOP and can substitute DOP up to 50% of plasticizer loading. J. VINYL ADDIT. TECHNOL., 23:152–160, 2017. © 2015 Society of Plastics Engineers

Azithromycin-molecularly imprinted polymer based on PVC membrane for Azithromycin determination in drugs using coated graphite electrode

Several molecular imprinted polymer (MIP) membranes for Azithromycin (Azin) coated on graphite electrodes were constructed based on PVC matrix. The Azin-imprinted polymers (MIP) were prepared by thermal polymerization using acrylic acid (AA) and 2-vinyl pyridine (VPY) as monomers, ethylene glycol dimethacrylate (EGDMA) as a cross linker in the presence of benzoyl peroxide (BPO) as an initiator. Two plasticizers di-butyl phosphate (DBP) and di-octyl phthalate (DOP) were used in this study. Electrode parameters such as Nernstian slopes, concentrations, pH and interferences were studied. The results of Azin-MIP electrodes, which based on AA and VPY as monomers with DBP plasticizer, show fully Nernstian slopes. For MIP electrodes using DOP plasticizer the slopes were 49.1 and 51.3mV/decade, respectively. Excellent detection limits for the electrodes around 10−7M were obtained. Life times of MIP were more than four months. The pH range for the electrodes from 3.0 to 8.0 shows no change in the electrode response and a response time around 30s was noticed for low concentrations of Azin. The effect of some cations and neutral species interferences on electrode response was also studied. Standard addition method using graphite MIP electrode was applied for Azin determination in commercial tablets and capsules of Azin drug. The results obtained by the MIP electrode were compared with the official spectrophotometric method. The binding capacity between polymer of AA as a monomer and Azin as a template was also investigated.

Construction and Potentiometric Study of Chloramphenicol Selective Electrodes Based on a PVC Matrix Membrane

Chloramphenicol succinate selective electrodes were prepared based on a complex Chloramphenicol succinate -phosphomolybdate as an active material using the plasticizers di-octyl phthalate (DOPH), tri-butyl phosphate (TBP), o-nitro phenyl octyl ether (ONPOE) and di-butyl phthalate (DBPH) in a PVC matrix membrane. The properties of the prepared electrodes were studied, such as: slope, concentration range, detection limit, lifetime, pH effect and selectivity. The experimental results showed that the best electrode was based on DOPH and DBPH as plasticizers, displaying a linear range from 1.00x10 −4 M to 1.00x10 −1 M and 1.00x10 −1 M to 2.00x10 −4 with a Nernstian slope of 58.5 mV/decade and 53.9 mV/decade, correlation coefficient of 0.9999 and 0.9998, The detection limit was 5.5x10 −5 M and 8.0x10 −5 , the lifetime was around 40 and 25 days respectively. The proposed electrodes were successfully applied to the determination of in Chloramphenicol succinate a pharmaceutical preparation. Keyword: Chloramphenicol; Ion-selective electrode; Potentiometry; Pharmaceutical analysis.

Cadmium (II) ion sensing through p-tert-butyl calix[6]arene based potentiometric sensor

Poly (vinyl chloride) (PVC) based membranes containing p-tert-butylcalix [6] arene (I) in the molecular form as an electroactive material along with anion excluder sodium tetraphenyl borate (NaTPB) and plasticizer Di-Octyl phthalate (DOP) have been used to fabricate a new cadmium-selective sensor. Out of the various compositions, the best performance was exhibited by the membrane having I-PVC-NaTPB-DOP in the ratio 1:33:1:65 (w/w). The sensor works well in the concentration range 9.7×10−5 to 1×10−1moldm−3 with a near-Nernstian slope of 29.0±1mV/decade of activity. The working pH range of this sensor is 2.8 to 6.2 and its performance was found satisfactory up to 20% non-aqueous medium. It exhibits a fast response time of 35s and could be used for more than 4months without any considerable change in response characteristics. It has excellent selectivity for Cd(II) over alkali, alkaline and other heavy metal cations.

Mechanical and morphological properties of acrylonitrile–butadiene–styrene terpolymer/nitrile butadiene rubber thermoplastic vulcanizates plasticized by dioctyl phthalate

Thermoplastic vulcanizates (TPVs) based on acrylonitrile–butadiene–styrene terpolymer (ABS)/nitrile butadiene rubber (NBR) blends were prepared by dynamic vulcanization where ABS matrix was plasticized by dioctyl phthalate (DOP), and the influences of DOP plasticizer dosage on mechanical properties, Mullins effect, and morphological properties of the TPVs were investigated systematically. Experimental results indicated that the mechanical properties of ABS/NBR TPVs were improved significantly with the incorporation of DOP. Compared with ABS/NBR TPVs, the tensile strength and the elongation at break went through maximum values at a plasticizer content of 10 phr, while the Shore A hardness was decreased apparently. Mullins effect results showed that the TPVs incorporated with DOP had relatively lower stress-softening effect, residual deformation, and internal friction loss than that of the ABS/NBR TPVs, indicating the improvement of elasticity. Morphology studies showed that the fracture surface of ABS/NBR/DOP TPVs was relatively smoother, indicating the significantly improved elastic resilience ability.

Enhanced Mathematical Modeling of DOP plasticizer migration from PVC into liquid (methanol)

Polyvinyl chloride, commonly abbreviated PVC is a rather hard and rigid material. In order to extend its use it requires additives during the manufacturing process which are referred to as plasticizers, among them the Dioctyl Phthalate (DOP). This latter has a tendency to escape from the PVC matrix specially when in contact with liquids. In order to analyse this phenomenon we use the classical equations of mass diffusion (Fick’s second law). However this method leads to results which are not always in good agreement with experimental ones, especially when the concentration of plasticisers is high. This situation requires the elaboration of an enhanced mathematical model that can deal with this particular type of forced diffusion characterized by the contact with a liquid and particular boundary conditions. The validation of the proposed model was obtained by comparing the theoretical results obtained with the model and those obtained by experiments.

Synthesis and characterization of a novel aliphatic polyester based on itaconic acid

A novel potentially biobased aliphatic polyester poly (butylene 2-methylsuccinate) (PBMS) was synthesized from 1,4-butanediol (BDO) and 2-methylsuccinate acid (MSA) via direct esterification and polycondensation route using tetrabutyl titanate (TBT) as catalyst. The reaction conditions were investigated in detail. The proper molar ratio (1.08:1) of BDO to MSA was determined through balancing the reaction efficiency and costs of reactants. TBT was found to be an effective catalyst, and its content (0.1 mol% of MSA) was optimized based on the esterification ratio and intrinsic viscosity. The molecular weight of PBMS polymers was governed by the polycondensation time. The weight average molecular (Mw) characterized by gel permeation chromatography (GPC) ranged from 5,800 to 8,700 g/mol. The polyester was also characterized by nuclear magnetic resonance spectroscopy (1H NMR), differential scanning calorimeter and thermogravimetric analysis. The results showed that the glass transition temperature continuously increased with molecular weight. The polyester had excellent thermal stability, and its decomposition temperature increased with the molecular weight. As new potentially biobased polyester plasticizer, desirable mechanical properties were achieved at the weight ratio of PBMS was 80/100 and 50/100. In addition, the PBMS/poly(vinyl chloride) (PVC) blends had superior migration-resistant property to the low-molecular weight plasticizer dioctyl phthalate for PVC. POLYM. ENG. SCI., 54:2515–2521, 2014. © 2013 Society of Plastics Engineers

A lead (II) selective PVC membrane potentiometric sensor based on a tetraazamacrocyclic ligand

A polymeric membrane based Pb(II) selective potentiometric sensor was developed by using 1,3,7,9-tetraaza-2,8-dithia-4,10-dimethyl-6,12-diphenylcyclododeca-4,6,10,12-tetraene (TDDDCT) as an electroactive material along with anion excluder sodium tetraphenylborate (NaTPB) and plasticizer dioctylphthalate (DOP). The best performance in terms of slope, concentration range and response time was exhibited by the membrane having TDDDCT:PVC:DOP:NaTPB in the ratio 3:32:62:3 (w/w%). Potentiometric results show that the developed sensor works well in the concentration range 5.0 × 10−7–1.0 × 10−1 M with a near Nernstian slope of 29.5 (±0.5) mV decade−1. The detection limit is down to 2.5 × 10−7 M. The working pH range of this sensor is 2.8–7.0 and it works well in partially nonaqueous medium up to 25 % (v/v) methanol and ethanol. It exhibits a fast response time of 10 s. Selectivity coefficient values of various interfering ions were determined by the fixed interference method (FIM). The sensor reveals good selectivity for Pb(II) ions over other metal ions investigated. The developed sensor is used in the determination of lead in ‘Eveready battery waste’ and as an indicator electrode in the potentiometric titration of Pb(II) against EDTA.

Thermal Properties, Degradation and Stability of Poly(vinyl chloride) Predegraded Thermooxidatively in the Presence of Dioctyl Phthalate Plasticizer

Thermooxidative degradation of poly(vinyl chloride) (PVC) is inevitable during its processing. Recycling of this polymer requires reprocessing in most cases, and due to the low thermal stability of PVC, it is of paramount importance to reveal the effect of thermooxidation on the thermal stability of this commercially important polymer. However, detailed systematic investigations are lacking on this crucial problem. In this study, the thermal behavior of PVCs thermooxidized in dilute dioctyl phthalate (DOP) (di(2-ethylhexyl) phthalate, DEHP) plasticizer was investigated by DSC, thermal gravimetry and isothermal degradation under inert atmosphere. It was found that thermooxidation leads to PVCs with certain extent of internal plasticization by DOP chemically bound to the PVC chains and by the oxidized chain segments as well. Thermogravimetry and isothermal dehydrochlorination under inert atmosphere revealed that even low extent of thermooxidation of PVC (0.4 mol% of HCl loss in 30 min at 200°C) leads to dramatically decreased thermal stability of this polymer with 50–60°C lower onset decomposition temperature than that of the virgin resin. This unexpected finding means that at least part of the oxidized moieties formed during oxidation of the PVC chains acts as initiators for thermal dehydrochlorination at relatively low temperatures, resulting in significant decrease of the thermal stability of the polymer. These striking results also indicate that the decreased thermal stability caused by thermooxidation in the course of the primary processing of this polymer should be taken into account in order to efficiently stabilize PVC products for reprocessing and recycling.