Revisiting analysis of phthalate plasticizers concentration in poly(vinyl chloride)

The method of the efficient analysis of di(2‐diethylhexyl) phthalate, tri(2‐ethylhexyl) trimellitate, di(2‐ethylhexyl) terephthalate, and other phthalate plasticizers concentrations in plasticized poly(vinyl chloride) (PVC) was developed. The method is based on quantitative dissolution of the PVC sample in methyl ethyl ketone with the consequent precipitation of PVC with hexane and concentration of phthalate in an organic layer. A capillary column‐based gas chromatographic technique for phthalates separation and quantification was developed and used in conjunction with the PVC and phthalates dissolution technique. The developed method of phthalate plasticizers analysis proved to be relatively fast, reproducible, and straightforward. J. VINYL ADDIT. TECHNOL., 21:197–204, 2015. © 2014 Society of Plastics Engineers     

Migration of phthalate and non‐phthalate plasticizers out of plasticized PVC films into air

The aim of the present work is to provide information about the migration of phthalate and non‐phthalate plasticizers generally used in flexible polyvinyl chloride (PVC) applications. Plastisols (pastes) were prepared by mixing PVC, plasticizer, and thermal stabilizer. The plasticized PVC (p‐PVC) films are obtained by gelation at 160°C for 15 min. The p‐PVC films were heat treated at 50, 85, 100, 130, and 160°C up to 420 min to follow the mass loss to find out diffusivity of plasticizer out of films into air and to determine related activation energies. The films having di‐octyl terephthalate (DOTP) and di‐isononyl 1,2‐cyclohexanedicarboxylic acid (DINCH) exhibited the lowest mass loss in general, among the phthalate and non‐phthalate plasticizer having p‐PVC films, respectively, as confirmed by FTIR investigation. The same tendency was observed for diffusion coefficients and for the activation energies of migration. The diffusion coefficients were found to be around 3.5 × 10^?18–2.1 × 10^?17 m²/sec for the studied plasticizers in PVC at 50°C and around 4.0 × 10^?15–9.9 × 10^?14 m²/sec at 160°C. The activation energies for 85–160°C interval were determined to be between 70 and 153 kJ/mol (0.72–1.58 eV) for the plasticizers used herein those could be treated as a homologous series as deduced from the related compensation factors. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Soft PVC foams: Study of the gelation,fusion, and foaming processes. II. Adipate,citrate and other types of plasticizers

Plasticized poly(vinyl chloride) (PVC) is one of the most useful polymeric materials on an industrial scale because of its processability, wide range of obtainable properties, and low cost. PVC plastisols are used in the production of flexible PVC foams. Phthalates are the most used plasticizers for PVC, and in a previous article (part I of this series), we discussed the influence of phthalate ester type plasticizers on the foaming process and on the quality of the foams obtained from the corresponding plastisols. Because the use of phthalate plasticizers has been questioned because of possible health implications, the objective of this work was to undertake a similar study with 11 commercial alternative plasticizers to phthalates. The evolution of the dynamic and extensional viscosity and the interactions and thermal transitions undergone by the plastisols during the heating process were studied. Foams were obtained by rotational molding and were characterized by the determination of their thermomechanical properties, density, and cell size distribution. Correlations were obtained between the molecular weight and structure of the plasticizer and the behavior of the corresponding plastisols. After the characterization of the final foamed product, we concluded that foams of relatively good quality could be prepared with alternative plasticizers for replacing phthalates. Several plasticizers {Mesamoll (alkylsulfonic phenyl ester), Eastman 168 [bis(2‐ethylhexyl)‐1,4‐benzenedicarboxylate], Hexamoll [di(isononyl) cyclohexane‐1,2‐dicarboxylate], Citroflex A4 acetyl tributyl citrate (ATBC), and Plastomoll (dihexyl adipate)} were found to be interesting alternatives in the production of soft PVC foams because they provided very good quality foams with properties similar to, or even better than, those obtained with phthalate plasticizers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis and application of a natural plasticizer based on cardanol for poly(vinyl chloride)

A natural plasticizer with multifunctional groups, similar in structure to phthalates, cardanol derivatives glycidyl ether (CGE) was synthesized from cardanol by a two‐step modification process and characterized by FT‐IR, ¹HNMR, and ¹³CNMR. The resulting product was incorporated to PVC (CGE/PVC), and plasticizing effect was compared with PVC incorporated with two kinds of commercial phthalate ester plasticizers bis (2‐ethylhexyl) benzene‐1,4‐dicarboxylate (DOTP) and diisononyl phthalate (DINP). Dynamic mechanical analysis and mechanical properties testing of the plasticized PVC samples were performed in order to evaluate their flexibility, compatibility, and plasticizing efficiency. SEM was employed to produce fractured surface morphology. Thermogravimetric analysis and discoloration tests were used to characterize the thermal stabilities. Dynamic stability analysis was used to test the processability of formulations. Compared with DOTP and DINP plasticized samples, CGE/PVC has a maximum decrease of 9.27% in glass transition temperature (T_g), a maximum increase of 17.6% in the elongation at break, and a maximum increase of 31.59°C and 25.31 min in 50% weight loss (T50) and dynamic stability time, respectively. The obtained CGE also has slightly lower volatility resistance and higher exudation resistance than that of DOTP and DINP. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42465.     

Synthesis and application of an alternative plasticizer Di(2‐Ethylhexyl)‐1,2‐cyclohexane dicarboxylate

Cyclohexane dicarboxylic acid esters are environmentally friendly and non‐toxic plasticizers, and have similar performance with phthalates which have potential toxicity to human health. In this article, di(2‐ethylhexyl)‐1,2‐cyclohexane dicarboxylate (DEHCH) was synthesized via esterification between hexahydrophthalic anhydride (HHPA) with iso‐octanol by using concentrated sulfuric acid as a catalyst. The effects of reaction parameters on esterification were studied by investigating the temperature, reaction time, molar ratio of iso‐octanol‐to‐HHPA, and catalyst content. Conversions of HHPA to esters were determined. Functional group analysis was conducted by using FTIR and ¹H‐NMR spectroscopy. PVC compounds after addition of the synthesized plasticizer DEHCH presented similar plasticizing performance with DEHP and DINCH, as demonstrated by comparisons of the results of mechanical properties, transparency, and volatilization and migration tests obtained for plasticized PVC compounds. DEHCH can also be considered as an alternative plasticizer for DEHP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39763.     

Dialkyl furan‐2,5‐dicarboxylates,epoxidized fatty acid esters and their mixtures as bio‐based plasticizers for poly(VInylchloride)

Dialkyl furan‐2,5‐dicarboxylates and epoxidized fatty acid esters (EFAE) of varying molecular weights and volatilities, as well as their mixtures, were investigated as alternative plasticizers for poly(vinylchloride) (PVC). The EFAE utilized were epoxidized soybean oil (ESO) and epoxidized fatty acid methyl ester (e‐FAME). All plasticizers were compatible with PVC, with plasticization efficiencies usually increasing with decreasing molecular weights of the plasticizers (except in the case of ESO, which was remarkably effective at plasticizing PVC, in spite of its relatively high molecular weight). In comparison with phthalate and trimellitate plasticizers, the alternatives generally yielded improved balance of flexibility and retention of mechanical properties after heat aging, with particularly outstanding results obtained using 30?50 wt % e‐FAME in mixtures with diisotridecyl 2,5‐furandicarboxylate. Although heat aging characteristics of the plasticized polymer were often related to plasticizer volatilities, e‐FAME performed better than bis(2‐ethylhexyl) 2,5‐furandicarboxylate, and bis(2‐ethylhexyl) phthalate of comparatively higher molecular weights. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42382.     

Evaluating effects of biobased 2,5‐furandicarboxylate esters as plasticizers on the thermal and mechanical properties of poly (vinyl chloride)

We synthesized 2,5‐furandicarboxylate esters [i.e., dibutylfuran‐2,5‐dicarboxylate, diisoamylfuran‐2,5‐dicarboxylate, and di(2‐ethylhexyl)furan‐2,5‐dicarboxylate] and investigated their potential application as plasticizers of commercial poly(vinyl chloride) (PVC) products. Fourier transform infrared analysis, mechanical tests, scanning electron microscopy investigation, differential scanning calorimetry analysis, dynamic mechanical thermal analysis, thermogravimetric analysis (TGA), melt flow rate (MFR) measurement, and plasticizer migration measurements were used to the evaluate the comprehensive properties of the blended products. The results of the tensile tests demonstrate that the blends exhibited antiplasticization and flexible plastic characteristics at 10 and 50 phr in PVC, respectively. Moreover, flexural and impact test data indicate that the three types of blends exhibited a similar tendency: the hardness decreased continuously as the amount of plasticizer increased. Their morphology indicated that all of the plasticizers had good compatibility with PVC. The resulting glass‐transition temperature of the investigated plasticizers was lower than that of pure PVC, and reduction was largest for the plasticizer with the highest molecular weight. TGA revealed that the thermal degradation of blended polymers occurred in three stages and that all of the blends were stable up to 180°C. Finally, the MFRs of all of the specimens indicated that the addition of a higher concentration of lower molecular weight biobased esters resulted in improved fluidity, but these compounds migrated more easily from the blends. Hence, 2,5‐furandicarboxylic acid derived from biomass has potential as a plasticizer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40938.     

Characterization of 1,5‐pentanediol dibenzoate as a potential “green” plasticizer for poly(vinyl chloride)

1,5‐Pentanediol dibenzoate (PDDB) was evaluated as a potential “green” plasticizer for poly(vinyl chloride) (PVC) at concentrations ranging between 20 and 80 parts by weight per hundred parts of resin. The results of glass transition temperature (T_g) and tensile tests of PDDB blends with PVC were compared with those for blends of the commercial plasticizers di(2‐ethylhexyl) phthalate (DEHP), di(ethylene glycol) dibenzoate (DEGDB), and di(propylene glycol) dibenzoate (DPGDB) in PVC. The depression in T_g and the tensile properties were comparable for a PDDB/PVC blend at a fixed composition to those of blends with DEHP, DEGDB, and DPGDB. The PDDB was subjected to biodegradation using co‐metabolism by the common soil bacterium Rhodococcus rhodochrous (ATCC 13808). After 16 days of growth, nearly all of the PDDB was degraded, and only small amounts of transient, unidentified metabolites were observed in the growth medium during the experiment. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers     

采用凝胶渗透色谱法分析医用PVC中增塑剂的种类及含量

在不对样品进行萃取分离等前处理的条件下,利用凝胶渗透色谱(GPC)示差(RI)-紫外(UV)双检测器连用测定医用PVC粒料中增塑剂的种类及含量.通过RI检测器可以确定粒料中PVC树脂、增塑剂环己烷1,2-二甲酸二异壬酯(DINCH)和环氧大豆油(ESO)的质量分数约分别为70.1%,22.6%和7.3%;通过UV检测器...     

Hybrid sol gel coating: A solution to prevent interactions between plasticized poly(vinyl chloride) and injectable drugs?

During the infusion of drugs with medical devices in plasticized poly(vinyl chloride) (PVC) release of plasticizers in the injectable solution and/or sorption of drugs on PVC may occur. Thus, patient safety and/or effectiveness of his therapy may be altered. In this study, we assessed the efficiency of a sol gel hybrid coating in preventing plasticizers' release (di‐(2‐ethylhexyl) phthalate (DEHP)) from PVC matrix and drug sorption into PVC. Remaining concentrations of drugs and plasticizer's concentration released after migration tests were assessed by liquid chromatography. Migration processes were followed by Fourier Transform Infrared – Attenuated Total Reflectance (FTIR‐ATR) spectroscopy and PVC surface changes were characterized by scanning electron microscopy (SEM). An evaluation of the mechanical properties of both uncoated and coated polymer was done. The hybrid coating protects PVC from plasticizers leaching. Sorption of drugs tested is also limited. However, the protection against plasticized PVC interactions isn't optimal, probably due to a degradation of the layer, as shown on SEM microphotographs. Furthermore improvements might provide an efficient barrier to advert risks impaired to PVC interactions, to provide patient care safety. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40145.     

An innovative plasticizer for sensitive applications

Di(isononyl) cyclohexane‐1,2‐dicarboxylate (HEXAMOLL® DINCH) is a new plasticizer for PVC. In the tests used, it has no indication of toxicity or genotoxicity; it is biodegradable; and it has low sensitizing properties. Its properties in PVC compare favorably to those of other plasticizers having well‐balanced properties. This plasticizer should be well‐suited for sensitive applications.     

Novel branched poly(ɛ‐caprolactone) as a nonmigrating plasticizer in flexible PVC: Synthesis and characterization

A series of hyperbranched poly(?‐caprolactone) (HPCLs, denoted as D_X) with different molecular weights were synthesized by the copolymerization of GPCL (PCL initiated by glycidol) and succinic anhydride. The chemical structure of D_X was characterized by ¹H‐NMR gel permeation chromatography and inherent viscosity, and D_X was used as the plasticizer for poly(vinyl chloride) (PVC) compared to traditional plasticizer di‐(ethylhexyl) phthalate (DEHP). The thermal properties, morphology, mechanical properties, and migration stabilities of PVC films were explored with differential scanning calorimetry, thermogravimetric analysis, scanning electron microscope, tensile, and migration tests. PVC/D₁ exhibited the best plasticization efficiency up to 107%, with enhanced tensile strength (18.5 MPa) and ultimate elongation (416%) compared to PVC/DEHP (11.5 MPa and 375%, respectively). PVC/D₁ exhibited remarkably high plasticization efficiency as compared to PVC/DEHP at a plasticizer concentration of PVC below 40 wt %. Moreover, the migration test for PVC/D_X films exhibited minimal plasticizers migration even at very harsh conditions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46542.     

Oligomeric isosorbide esters as alternative renewable resource plasticizers for PVC

Oligo(isosorbide adipate) (OSA), oligo(isosorbide suberate) (OSS), and isosorbide dihexanoate (SDH) were synthesized and evaluated as renewable resource alternatives to traditional phthalate plasticizers. The structure of the synthesized oligomers was confirmed by nuclear magnetic resonance spectroscopy (¹H‐ and ¹³C‐NMR), and molecular weight was determined by size exclusion chromatograph. The plasticizers were blended with poly(vinyl chloride) (PVC), and the miscibility and properties of the blends were evaluated by differential scanning calorimetry, fourier transform infrared spectroscopy, tensile testing, and thermogravimetry. Especially the blends plasticized with SDH had almost identical properties with PVC/diisooctyl phthalate (DIOP) blends. The blends containing OSA and OSS plasticizers, based on dicarboxylic acids, had somewhat lower strain at break but higher stress at break and better thermal stability compared to the PVC/DIOP or PVC/SDH blends. All the synthesized isosorbide plasticizers showed potential as alternative PVC plasticizers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The strong interaction between poly(vinyl chloride) and a new eco-friendly plasticizer: A combined experiment and calculation study

Hydrogenation has been proved to be an efficient way to remove the toxicity of phthalate plasticizer. However, other influences of this hydrogenation are still unknown. Here we chose di-2-ethylhexyl phthalate (DOP) and di(2-ethylhexyl) cyclohexane-1,2-dicarboxylate (DEHHP) to study the influence on interaction with poly(vinyl chloride) (PVC). By combining experiment and calculation, we found the interaction was stronger in PVC/DEHHP than in PVC/DOP. Low-Field ¹H NMR results showed that PVC chains could restrict much more DEHHP molecules than DOP. FTIR results showed that the interaction exists in form of hydrogen bonding complex, and it was stronger in PVC/DEHHP than in PVC/DOP system. Combined with FTIR results, theoretical calculation results revealed the three-center hydrogen bonded structure of the complex. Both the proportion and the binding energy of pre-complex in DEHHP are much larger than in DOP. Here, the hydrogenation-induced change of interaction was elucidated systematically and could be generalized to other phthalate plasticizers.     

Benzyl ester of dehydrated castor oil fatty acid as plasticizer for poly(vinyl chloride)

The poly(vinyl chloride) (PVC) industry plays an important role in today's total plastics industry. The major volume of PVC is used as soft and plasticized PVC. PVC applications consume approximately 80% of the total production of plasticizers. Most of the common plasticizers are aromatic esters of phthalic acid. In the majority of countries, phthalate plasticizers are banned due to their carcinogenic properties. The concern raised about toxicity led to a large demand for bio‐based non‐toxic plasticizers. Hence, there is an increasing interest in replacing the phthalate plasticizers with those produced from simple bio‐based materials. Dehydrated castor oil fatty acid (DCOFA) is a renewable resource which can be esterified and used as an environment friendly plasticizer for PVC. Benzyl ester (BE) was prepared by reacting DCOFA with benzyl alcohol in the presence of catalyst at 170–180 °C. Esterification was further confirmed by acid value, hydroxyl number, ¹H NMR and Fourier transform IR spectroscopy. The modified plasticizer was used in various proportions as a co‐plasticizer in PVC for partial replacement of dioctyl phthalate (DOP). With an increase in the proportion of BE in PVC samples, a good plasticizing performance was observed. The incorporation of BE also resulted in a reduction in viscosity and viscosity pick‐up and improved mechanical, exudation, thermal degradation and chemical resistance properties. The presence of BE showed a reduction in the whiteness index due to presence of conjugated double bonds in the structure. The results of DSC, XRD and Shore hardness studies showed no significant variation in properties compared with those of DOP‐plasticized sheets and thus we can conclude that BE can be used as a co‐plasticizer in PVC. © 2013 Society of Chemical Industry     

Effect of biobased plasticizers on thermal,mechanical, and permanence properties of poly(vinyl chloride)

Phthalates can be replaced by other harmless and environmentally friendly plasticizers, such as isosorbide diesters (ISB), and epoxidized sunflower oil (ESO), which has been proved an efficient stabilizer for poly (vinyl chloride) (PVC) in helping to prevent degradation during processing. Formulations based on PVC with different amounts of ISB, ESO, and di‐(2‐ethylhexyl) phthalate (DEHP) from 0 to 60 parts by weight per hundred parts of resin were realized. To make PVC flexible with partial amounts of the debated phthalates as plasticizers, we use a combination of DEHP, ISB, and ESO. Effects of these two biobased plasticizers, ISB and ESO, and their mixture with DEHP on thermal stability by measuring discoloration degrees and thermal gravimetric analysis, on mechanical properties such tensile strength, elongation at break, and hardness, were characterized. Plasticizer permanence properties of PVC compounds were studied. Studies showed that processibility and flexibility were improved by the addition of a plasticizer system (ISB, ESO, and DEHP). An increase in the content of ISB and/or ESO increased thermal and mechanical properties, whereas compositions with ternary compositions of ISB/ESO/DEHP (15/15/30) exhibited the best performance properties. J. VINYL ADDIT. TECHNOL., 20:260–267, 2014. © 2014 Society of Plastics Engineers     

Evaluation of the effects of acetyl tributyl citrate as bio‐based plasticizer on the physical,thermal, and dynamical mechanical properties of poly(vinyl chloride)/polymethyl methacrylate blends

This article details our work in studying the plasticization of Poly(vinyl chloride) (PVC)/Polymethyl methacrylate (PMMA) blends with bio‐based acetyl tributyl citrate (ATBC) in place of conventional plasticizers such as di(2‐ethylhexyl) phthalate. PMMA was blended with PVC in various ratios from 0 to 100 wt% by melt compounding with or without the plasticizer ATBC. Both the glass transition temperatures of the blends (differential scanning calorimetry) and Tα (dynamic mechanical thermal analysis) are consistent with a miscibility of the components, and Fourier transforms infrared spectroscopy studies show that there are specific interactions in the PVC/PMMA blends favoring the miscibility. The thermal degradation of the blends was studied by thermogravimetric analysis that shows the thermal degradation of rigid and plasticized PVC/PMMA is a process composed of two‐steps and that PMMA exercises a stabilizing effect on the thermal degradation of PVC during the first step by decreasing the rate of dehydrochlorination. J. VINYL ADDIT. TECHNOL., 25:E73–E82, 2019. © 2018 Society of Plastics Engineers     

Effects of poly(1,2‐propylene glycol adipate) and nano‐CaCO3 on DOP migration and mechanical properties of flexible PVC

Nano‐CaCO₃ was used as nano‐scale filler and poly(1,2‐propylene glycol adipate) (PPA) was used as polymeric plasticizer in flexible poly(vinyl chloride) (PVC) sheets for the partial replacement of di(2‐ethyl hexyl) phthalate (DOP) in this paper. The effect of PPA and nano‐CaCO₃ on restraining DOP migration was evaluated via extraction tests. The results showed that the introduction of nano‐CaCO₃ can decrease the extraction rate of DOP in the PVC matrix. The tensile strength and elongation at break of CaCO₃‐1/PPA‐20/DOP‐30/PVC were similar to those of DOP‐50/PVC, and CaCO₃‐1/PPA‐20/DOP‐30/PVC exhibited the superior suppression of DOP migration compared with DOP‐50/PVC. Thermogravimetry analysis (TGA) indicated that the addition of nano‐CaCO₃ effectively improved the thermal stability of the nanocomposites. Therefore, the combination of PPA and nano‐CaCO₃ is an effective approach to suppress the migration of DOP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Photocrosslinking of azidated poly(vinyl chloride) coated onto plasticized PVC surface: Route to containing plasticizer migration

The migration of phthalate esters which are commonly employed for plasticizing poly(vinyl chloride) (PVC) is a significant problem in PVC-based medical devices as well as in packaging used for food stuffs and pharmaceuticals. Medical-grade PVC resin was treated with sodium azide in dimethylformamide (DMF) to prepare the azide polymer. The polymeric azide was coated onto the surface of plasticized PVC sheets by dipping in a solution of the polymer in tetrahydrofuran (THF). Crosslinking of the azide polymer was accomplished by irradiating the surface using a 125 W UV lamp for various lengths of time. Migration of the plasticizer di 2-(ethylhexyl phthalate) (DEHP) from coated and uncoated samples was examined in n-hexane at 30°C. It was found that 50–80% reduction in migration of DEHP could be effected from plasticized PVC in comparison with the controls in 72 h by this technique depending on the concentration of the coating solution, coating thickness, azide concentration, and irradiation dose. © 1995 John Wiley & Sons, Inc.     

Recycling of Waste PET: Usage as Secondary Plasticizer for PVC

Postconsumer water bottle poly(ethylene terephthalate) (PET) flakes were depolymerized with ethylene glycol (EG) by the glycolysis reaction in the presence of zinc acetate as the catalyst. In the depolymerization reactions, different weight ratios of PET/EG were used. In order to obtain polyesters used as PVC plasticizers, these glycolysis products containing hydroxyl end groups were reacted with an adipic acid (AA)–containing diacid group at equivalent amounts. In order to obtain PVC plastisols, PVC was dispersed into a plasticizers' mixture composed of di-isooctyl phthalate (DOP) and polyester products by using a high-speed mixer (PVC/plasticizers, 65/35 w/w). For the preparation of plasticizer mixture polyester products were used at a weight ratio of 20%, 40%, 60% of DOP. Plasticized PVC sheets were prepared from plastisols and their glass transition temperatures (T_g), migration, and mechanical properties were determined. The results show that the polyester products obtained from glycolysis products of waste PET can be used as secondary plasticizers, with DOP for PVC.