PVC Blends Research Articles

Biobased Plasticizers from Tartaric Acid: Synthesis and Effect of Alkyl Chain Length on the Properties of Poly(vinyl chloride).

A series of tartaric acid (TA) esters with different side chain lengths [dibutyl TA esters (DBTAE)-Cn], as plasticizers for poly(vinyl chloride) (PVC), is herein reported. Their structures have been fully characterized using proton nuclear magnetic resonance and Fourier-transform infrared spectroscopy. Their compatibility and plasticizing effect for soft PVC were evaluated using thermogravimetric analysis, dynamic mechanical analysis, tensile testing, and migration testing. The results showed that all these TA esters exhibit good plasticizing performance. At a concentration of 30 phr in PVC, the best results for the plasticizing effect, in terms of glass transition temperature reduction and elongation at break, were achieved when the ester DBTAE-C4 was used. However, the longer side chains of these esters improved the thermal stability of soft PVC blends yet exacerbated the migration behavior of these esters from PVC films in n-hexane. The properties of the plasticized PVC blends depended on the structural features of DBTAE-Cn. The plasticizing performances of the esters DBTAE-C1 and DBTAE-C4 rivaled that of dioctyl phthalate (DOP), suggesting that they have the potential to replace DOP in soft PVC materials.

Photostabilization of Poly(vinyl chloride) Films Blended with Organotin Complexes of Mefenamic Acid for Outdoor Applications

This study develops a process for enhancing the photostabilization of PVC films blended with a low concentration of mefenamate–tin complex. One tri-substituted and three di-substituted organotin complexes containing mefenamate unit are synthesized, and their chemical structures are established. The reactions of mefenamic acid and a number of substituted tin chlorides gave the corresponding tin complexes in 70–77% yields. Tin complexes were blended with PVC and thin films. The effect of the addition of additives against long-term irradiation (290–400 nm, 300 h) is also tested. Changes in the infrared spectra, weight, and surface of the PVC blends due to irradiation are examined and analyzed. Any damage to the PVC surface and its chemical degradation level are noticeably low in the presence of additives. Minimal photodegradation levels and surface changes of the irradiated PVC films are observed when the triphenyltin complex is used. Such a complex is highly aromatic and can act as an ultraviolet irradiation absorber and a scavenger for hydrogen chloride and radicals produced due to the photooxidation and photoirradiation of PVC films.

Recent Attempts in the Design of Efficient PVC Plasticizers with Reduced Migration

This paper reviews the current trends in replacing commonly used plasticizers in poly(vinyl chloride), PVC, formulations by new compounds with reduced migration, leading to the enhancement in mechanical properties and better plasticizing efficiency. Novel plasticizers have been divided into three groups depending on the replacement strategy, i.e., total replacement, partial replacement, and internal plasticizers. Chemical and physical properties of PVC formulations containing a wide range of plasticizers have been compared, allowing observance of the improvements in polymer performance in comparison to PVC plasticized with conventionally applied bis(2-ethylhexyl) phthalate, di-n-octyl phthalate, bis(2-ethylhexyl) terephthalate and di-n-octyl terephthalate. Among a variety of newly developed plasticizers, we have indicated those presenting excellent migration resistance and advantageous mechanical properties, as well as those derived from natural sources. A separate chapter has been dedicated to the description of a synergistic effect of a mixture of two plasticizers, primary and secondary, that benefits in migration suppression when secondary plasticizer is added to PVC blend.

Piezoelectric and pyroelectric properties of ceramic nanoparticles-based nanostructured PVDF/PVC blend nanocomposites

BaZrO3 and BaTiO3 nanofillers were incorporated in pristine PVDF and pristine PVC blend matrix separately to prepare blend nanocomposites using the solution casting technique. The mass ratios of PVDF/PVC/BaTiO3 were chosen to be 80/16/4. The structure morphology of nanocomposites was analyzed by Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and X-ray diffraction. The FTIR, AFM, XRD and pyroelectric results indicate the strong interaction between the nanofiller and PVDF/PVC blend matrix. The nanocomposite exhibits a high pyroelectric coefficient due to proper dispersion of nanofillers. The maximum piezoelectric coefficients (d33) were 39, 88, 79.72, 112pC N−1 for pristine PVC, pristine PVDF, PVDF/PVC/BaZrO3 and PVDF/PVC/BaTiO3 blend nanocomposites, respectively. The remnant polarization of blend nanocomposites is also measured by P–E loop. P–E loop shows that the polarization of the blend nanocomposites increases under influence of nanofiller. The pyroelectric coefficient for PVDF/PVC/nanofiller blend nanocomposite is very sensitive in the temperature range of 30 to 180 °C and greater than PVC (i.e. 351 µC m−2 K−1 > 15 µC m−2 K−1).

Renewable malic acid-based plasticizers for both PVC and PLA polymers

Acetylated malic acid alkyl esters (AcMAE-Cn) with different alkyl chain lengths, as alternative plasticizers for both poly(vinyl chloride) (PVC) and poly(lactic acid) (PLA), were synthesized by the esterification of renewable malic acid with alcohols and subsequent acetylation. The molecular structure of the synthesized plasticizers was confirmed using 1H NMR and FT-IR spectroscopy. PVC or PLA blends containing 50phr of the plasticizers were evaluated by dynamic mechanical analysis (DMA), tensile testing, and migration testing to evaluate the plasticization efficiency. The plasticized PVC films presented good plasticizing performance, as demonstrated by the results of tensile and migration testing and the Tg values (as determined by DMA). Among the plasticizers, AcMAE-C6 and AcMAE-C8 presented enhanced plasticizing performance compared with that of the commercial dioctyl adipate (DOA) and di(2-ethylhexyl) phthalate (DEHP) plasticizers. Additionally, the plasticizing properties of the plasticized PLA films depend significantly on the structure of the plasticizers. It was found that plasticizers (AcMAE-C4 and AcMAE-C6) bearing short alkyl groups (n-butyl and n-hexyl, respectively) may act as excellent plasticizers. In summary, the AcMAE-C6 plasticizer showed potential as an alternative plasticizer for both PVC and PLA polymers.

Synthesis of a Novel Bio-Oil-Based Hyperbranched Ester Plasticizer and Its Effects on Poly(vinyl chloride) Soft Films.

A novel hyperbranched ester plasticizer (SOHE) was synthesized from soybean oil. FTIR, 1H NMR, and 13C NMR spectroscopies were used to analyze the chemical structure of SOHE. SOHE was added into poly(vinyl chloride) (PVC). Thermal, mechanical, and dynamic mechanical properties of PVC samples were studied with thermal gravimetric analysis, dynamic mechanical analysis, and tensile tests. The results of SOHE substitution of petroleum-based dioctyl phthalate (DOP) in soft PVC samples were studied. The results indicated that PVC blends mixed with the obtained plasticizer showed higher thermal stability and flexibility. When DOP was completely replaced with SOHE, the Ti, T10, and T50 of the films were raised to 267.5, 275.3, and 338.0 °C, respectively. The plasticizing mechanism was also investigated. The volatility resistance and extraction were studied, which results indicated that the migration stability of PVC samples was significantly enhanced with the increasing amount of SOHE.

Synthesis and application of a novel thermostable epoxy plasticizer based on levulinic acid for poly(vinyl chloride)

AbstractEpoxy bisphenol acid isooctyl ester (EBAIE) was synthesized and characterized by FTIR and H‐NMR. EBAIE was used as poly(vinyl chloride) (PVC) plasticizer for the first time, and its addition amount was 30 wt% of PVC. The mechanical properties, thermal stability, compatibility, and decomposition activation energy of PVC blends were systematically studied. Compared to the commercial plasticizer‐dioctyl phthalate (DOP), the tensile strength had been significantly increased from 30.64 to 45.07 MPa, while the elongation at break had little difference. The thermal stability analysis showed that the static stability time at 180°C had been extended from 40 to 300 min. The decomposition activation energy indicated that the EBAIE plasticized PVC was with a higher thermal stability. The extraction and volatility resistance of the novel plasticizer were superior to those of DOP.

Replacing Di(2-ethylhexyl) Terephthalate by Di(2-ethylhexyl) 2,5-Furandicarboxylate for PVC Plasticization: Synthesis, Materials Preparation and Characterization.

The worldwide regulatory demand for the elimination of non-phthalate compounds for poly(vinyl chloride) (PVC) plasticization has intensified the search for alternatives. Concomitantly, sustainability concerns have highlighted sugar-based 2,5-furandicarboxylic acid as one key renewable-chemical for the development of several products, namely di(2-ethylhexyl) 2,5-furandicarboxylate (DEHF) plasticizer. This study addresses the use of DEHF under a realistic scenario of the co-existence of both DEHF and entirely fossil-based plasticizers. More precisely, original PVC blends using mixtures of non-toxic DEHF and di(2-ethylhexyl) terephthalate ester (DEHT) were designed. The detailed structural, thermal, and mechanical characterization of these materials showed that they all have a set of interesting properties that are compatible with those of commercial DEHT, namely a low glass transition (19.2–23.8 °C) and enhanced elongation at break (up to 330%). Importantly, migration tests under different daily situations, such as for example exudation from food/beverages packages and medical blood bags, reveal very low weight loss percentages. For example, in both distilled water and phosphate buffered saline (PBS) solution, weight loss does not exceed ca. 0.3% and 0.2%, respectively. Viability tests show, for the first time, that up to 500 μM of DEHF, a promising cytotoxic profile is observed, as well as for DEHT. Overall, this study demonstrates that the combination of DEHF and DEHT plasticizers result in a noticeable plasticized PVC with an increased green content with promising cytotoxic results.

Characterization of the compatibility of PVC/PLA blends by Aid of Rheological Responses

Among many characterization methods for the compatibility of blends, the rheological ones have attracted more and more attention due to its sensitive response to the changes of structure of blends. In this work, PVC and PLA blends were prepared by melt mixing in torque rheometer. Static and dynamic rheological responses were used to analyze the compatibility of PLA/PVC blends, and a variety of analytical methods were also used, such as SEM and DSC, to assist revealing the phase morphology of the blends. The results showed that PVC/PLA = 50/50 formed a co-continuous phase structure, the other ratio blends formed a “sea-island" structure. The blend with co-continuous structure exhibited the lowest viscosity, the highest non-Newtonian index and the lowest entrance pressure drop, and the phase separation was more difficult than those with “sea-island" structures. It was concluded that the blend with co-continuous phase structure showed the strongest rheological responses. PVC/PLA = 50/50 also showed the highest impact strength among the blends.

Application of a bio‐based polyester plasticizer modified by hydrosilicon‐hydrogenation reaction in soft PVC films

A kind of bio‐based plasticizer, poly (hexanediol maleic) (MH), was synthesized using 1,6‐hexalene and maleic acid as raw materials, and it was modified by hydrosilicon‐hydrogenation reaction to improve its plasticizing efficiency. The chemical structure and plasticizing performance of MH and its modification product (MHA) were characterized by Fourier‐transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H‐NMR), X‐ray photoelectron spectroscopy (XPS), and Dynamic mechanical analysis (DMA). It was found that the hydrosilicon‐hydrogenation modification effectively improved the plasticizing efficiency of MH, reflecting on the decreased Tg and the increased elongation at break of PVC blends. The migration resistance of PVC blends was tested and analyzed by solubility parameters, which revealed that the migration stabilities of PVC blends were promoted after modification. It was verified that the hydrogen bonding interaction between the CO group of plasticizers and α‐hydrogen of PVC exhibited in FTIR analysis was the main reason for the improvement of plasticizer performance of MH. Moreover, a new hydrogen bonding formed between SiOSi of MHA and the α‐hydrogen of PVC derived from XPS also caused the further improvement of plasticity for MHA.

Effect of the molecular weight on the plasticization properties of poly(hexane succinate) in poly(vinyl chloride) blends

ABSTRACTBlends of poly(vinyl chloride) (PVC) and poly(hexane succinate) (PHS) with various molecular weights were analyzed with respect to their mechanical properties, durability, and thermal stability. We found that the molecular weight of PHS played an important role in the plasticizing process, and the single glass‐transition temperature (T g) of the PVC blends measured by dynamic mechanical analysis supported the complete miscibility between PHS and PVC. The plasticizing efficiency of PHS increased as the molecular weight increased; this reflected the gradually increasing elongation at break and the decreased T g of the PVC blend. Meanwhile, the higher molecular weight of PHS also improved the resistance of migration and thermal stability but decreased the biodegradability of the PVC blends; this was due to the strong intermolecular interactions between PHS and PVC. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47081.

Lipase immobilization on high water adsorbing capacity bagasse: applications in bio-based plasticizer synthesis.

This study investigates the structure and water adsorbing capacity of bagasse and of sodium hydroxide pretreated bagasse. The structures of bagasse and bagasse-NaOH were compared by SEM and XRD. Candida antarctica lipase B was then immobilized on bagasse, bagasse-NaOH and DPA@bagasse-NaOH. The expressed activity and immobilization yield of lipase immobilized on bagasse-NaOH (1.0%) was 36% and 45% higher than that on bagasse. When dopamine (DPA) was used as cationic polymer monomer via self-polymerization for mediating immobilization, the protein loading amounts and activity of lipase immobilized on DPA@bagasse-NaOH were higher than that of bagasse-NaOH. When the DPA concentration was 100mg/ml, the immobilized lipase expressed activity reached its highest value (800 U/g), where the immobilization yield achieved 96.8%, which was 3.93-fold of lipase immobilized on native bagasse (24.6%). Then the immobilized lipases were used to synthesize a bio-based plasticizer. Lipase immobilized on DPA@bagasse-NaOH exhibited a significantly improved operational stability. Even after 12 batches, a high ester yield (84.2%) was maintained. Additionally, poly (vinyl chloride) PVC blends plasticized with methyl oleate as a secondary plasticizer were investigated. It was discovered that methyl oleate can be used as an effective bio-based plasticizer for PVC. These results indicate that bagasse with high water adsorbing capacity and self-polymerized DPA layer could create a favorable microenvironment for bio-based plasticizer synthesis in esterification reactions.

Designing Green Plasticizers: Linear Alkyl Diol Dibenzoate Plasticizers and a Thermally Reversible Plasticizer.

Several linear alkyl diol dibenzoate compounds, ranging from C3 to C6 in central diol length, were evaluated for their plasticizing effectiveness in blends with poly(vinyl chloride) (PVC). The results were compared to blends of PVC/di(2-ethylhexyl) phthalate (DEHP), the most commonly used commercial plasticizer. DEHP has come under scrutiny, due to its suspected endocrine-disrupting behaviour, and the proposed diol dibenzoates have previously been shown to have the potential to be green, safe candidates for DEHP replacement. The thermal and mechanical properties of PVC/dibenzoate blends were determined, and include glass transition temperature (Tg), the elongation at break, maximum stress, apparent moduli, torsional modulus, and surface hardness. The C3, C5, and C6 dibenzoates performed as well as or better than DEHP, with the exception of torsional modulus, further supporting their use as green plasticizers. For blends with 1,4-butanediol dibenzoate, differential scanning calorimetry and torsional temperature sweeps suggested that the compound partly crystallizes within PVC blends over the course of two days, thereby losing the ability to effectively plasticize PVC. However, upon heating to temperatures above 60 °C, effective plasticization was again observed. 1,4-Butanediol dibenzoate is thereby a reversible heat-activated plasticizer or processing aid with excellent plasticizer properties at mildly elevated temperatures.

Synthesis of a novel environmental friendly plasticizer based on tung oil fatty acid for poly (vinyl chloride) blends

Abstract A novel environmental friendly plasticizer (TPE) derived from tung oil fatty acid with long fatty acid chain and high degree of branching was synthesized. Chemical structure of the obtained TPE was characterized with Fourier transform infrared spectroscopy (FT-IR) and 1H NMR. TPE was used to prepare plasticized PVC blends as main plasticizer. Thermal stability, mechanical properties and migration resistance of poly (vinyl chloride) plasticized with TPE were investigated. The results showed that torque data of plasticized PVC blends reached 12.4 N·m when the mass of the TPE was 50 wt.%. TPE improved the thermal stability of PVC blends obviously than dioctyl phthalate (DOP). The leaching tests showed that PVC plasticized with TPE were with higher migration resistance than that of DOP. The excellent thermal stability and high migration resistance of PVC blends showed high application value for TPE.

Influence of MWCNT on the Processing Properties and Structure of PVC Composites

The preparation of nanocomposites by incorporation of nanoparticles, in particular the carbon nanotubes in a molten polymeric matrix could find potential application in industry technologies as a method of the manufacturing of new engineering materials. Considering the complex transformations of PVC grains during processing as well as weak dispersibility of nanotubes caused by their high tendency to agglomeration are crucial to investigate the influence of MWCNT content on PVC processability. For this purpose the plastographmetric analysis of processing of PVC/MWCNT blends are carried out. The results of the research show that the presence of nanotubes causes an increase in shearing stress, which leads to PVC grains disintegration and faster gelation compared to the unmodified PVC blend. At the same time, the carbon nanotubes dispersed in the molten PVC blend lead to intensification of the process, which occurs at a lower temperature.

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 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.

Fabrication of immobilized powdered activated carbon as a sub-layer of TiO2 for the photocatalytic-adsorptive removal of phenol

A highly effective and reusable immobilized powdered activated carbon (PAC) was fabricated on the glass plate via a dip-coating technique to remove aqueous phenol. This immobilized PAC layer would become a sub-layer of TiO2 in the TiO2/PAC layer by layer system. The immobilized PAC was characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and Brunauer, Emmett and Teller surface area (S BET ). FTIR spectra showed that PAC did not form any crosslinking reaction with ENR–PVC blend when both materials were mixed while PAC particles were enwrapped with ENR–PVC, which reduced the S BET from 620.3 to 317.5 m2 g−1. It was found that the thickness of immobilized PAC increased proportionally with loadings with improved removal efficiency. Preliminary efficiency tests on immobilized TiO2/PAC layer by layer system under indoor lamp and solar irradiation for phenol removal proved that the immobilized PAC was a suitable sub-layer adsorbent for TiO2.

Synthesis of Tung-Oil-Based Triglycidyl Ester Plasticizer and Its Effects on Poly(vinyl chloride) Soft Films

A tung-oil-derived renewable plasticizer, tung-maleic triglycidyl esters (TMTE), was prepared and incorporated into poly(vinyl chloride) (PVC) for the first time. The chemical structure was studied by Fourier transform infrared (FTIR), 1H nuclear magnetic resonance (NMR), and 13C NMR. The plasticizing effects of TMTE replacement of dioctyl phthalate (DOP) in soft PVC films were researched. Thermal stability, thermal degradation performance, dynamic mechanical property, and mechanical properties of pure PVC and PVC films were investigated with thermogravimetric analysis (TGA), TGA-FTIR, TGA-mass spectrometry, dynamic mechanical analysis, and mechanical test. The results showed that PVC films plasticized with the TMTE exhibited increased thermal stability, plasticizing effect, compatibility, and flexibility. When 30 phr (parts per hundred parts of resin) DOP was substituted with TMTE in PVC blends, glass transition temperature (Tg) dropped from 41.46 to 40.18 °C, the initial decomposition temperature (Ti), ...

Synthesis and characterization of poly(styrene sulfonic acid-co-1-vinylimidazole-co-styrene) and its blends with poly(vinyl chloride) as proton conducting membranes

The development of proton conducting membranes based on poly(styrene sulfonic acid-co-1-vinylimidazole-co-styrene) (PSSA-co-PVIm-co-PS)/poly(vinyl chloride) (PVC) blends is firstly reported. PSSA-co-PVIm-co-PS with three different terpolymer compositions were synthesized via conventional free radical polymerization by varying styrene feed. Successful syntheses were confirmed by 1H-nuclear magnetic resonance spectroscopy (1H-NMR), elemental analysis, and Fourier transform infrared spectroscopy (FTIR). Hydrolytically stable PSSA-co-PVIm-co-PS/PVC blend membranes were prepared via solution-cast method. Scanning electron microscopy (SEM) images along with two glass transition temperatures observed from differential scanning calorimetry (DSC) suggested immiscible polymer blends. Water uptake and ion exchange capacity (IEC) were found to decrease with increasing PS content in terpolymer. All blend membranes had high thermal decomposition onsets of 230 °C. The blends demonstrated high storage moduli at room temperature and high oxidative stability. Proton conductivity at 25 °C of membranes equilibrated with water vapor was found to depend on PS content, and a maximum conductivity of 7.8 × 10−5 S/cm was achieved from 1:1:4/PVC blend membrane. For dry membranes, the effect of PS amount on proton conduction was not clearly observed at elevated temperatures (100–120 °C).