Mechanical and barrier properties of polyvinyl chloride plasticized with dioctyl phthalate,epoxidized soybean oil,and epoxidized cardanol

Plasticized polyvinyl chloride (PVC) films were prepared by melt compounding and compression molding using epoxidized cardanol (EC), a biobased plasticizer and its plasticization effect was compared with epoxidized soybean oil (ESBO) and dioctyl phthalate (DOP). The mechanical, migration, thermal, and barrier properties of the plasticized films were compared. The effect of replacing DOP with EC on the properties of PVC films was also investigated. The tensile strength, elongation at break, tensile modulus and impact strength values of PVC/EC films were higher in comparison to PVC/DOP and PVC/ESBO films at a fixed plasticizer loading of 40 wt.%. Also, the films prepared with a mixture of DOP + EC showed higher tensile strength and elongation at break compared to that of films prepared with only DOP. The PVC/EC films showed good thermal stability and reduced oxygen transmission rate (OTR) compared to PVC/DOP films. The addition of graphene and nanoclay in the PVC/plasticizer system exhibited an increase in oxygen transmission. However, the oxygen barrier property of nano filler incorporated PVC/EC films was better than PVC/DOP films. All the films showed negligible water vapor transmission rate (WVTR).     

Oil-resistance studies of dynamically vulcanized poly(vinyl chloride)/epoxidized natural rubber thermoplastic elastomer

Dynamically vulcanized poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) thermoplastic elastomers (TPEs) were prepared with a Brabender plasticorder coupled with a mixing attachment by melt mixing. The blends were prepared at 150°C at a rotor speed of 50 rpm. Curatives concentration was steadily increased from 0 to 1 phr in order to study the vulcanization effect on the plasticized blend. The effectiveness of the dynamic vulcanization was indicated by the Brabender plastograms. The properties investigated include mass swell, tensile strength, elongation at break, modulus at 100% elongation (M100), tear strength, and hardness. The PVC/ENR samples were exposed to two types of environments, namely, air and oil under otherwise identical conditions. The effect of oil and thermooxidative aging on the mechanical properties were characterized at room temperature and 100°C. It was found that at ambient temperature the samples immersed in oil possessed similar properties to those that were exposed to air. Significant enhancement in mechanical properties were observed for both environments at 100°C. This has been attributed to the increase in crosslink density which was manifested by a steady reduction in percent mass swell with increased sulfur loading. The excellent mechanical behavior of the PVC/ENR TPEs even after immersing the samples in oil at 100°C has provided a good indication of the oil resistance of the materials. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1357–1366, 1998     

Effects of epoxidized sunflower oil on the mechanical and dynamical analysis of the plasticized poly(vinyl chloride)

Epoxidized soybean oil (ESBO), is one of the most commonly used epoxides because of its typical combined roles as a plasticizer and heat stabilizer. In this study, a novel plasticizer of poly(vinyl chloride) (PVC) resins, epoxidized sunflower oil (ESO), was synthesized, and its performance was evaluated. ESO was designed to act as a coplasticizer and a heat stabilizer like ESBO. ESO is used as organic coplasticizer for plasticized PVC containing Ca and Zn stearates as primary stabilizers and stearic acid as lubricant. Di‐(2‐ethylhexyl) phthalate (DEHP), a conventional plasticizer for PVC, was partially replaced by ESO. Mechanical properties (tensile and shore D hardness) were investigated. The performance of ESO to ESB0 (20 g) for comparison, indicated that ESO could be used as secondary plasticizer for PVC in combination with DEHP. All mechanical and dynamical properties of plasticized PVC sheets varied with the oxirane oxygen of the ESO. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

The effect of di-2-ethylhexyl phthalate on the thermo-oxidative ageing of poly(vinyl chloride)/epoxidized natural rubber blends

The effect of di-2-ethylhexyl phthalate (DOP) plasticizer on the degradation behaviour of 50/50 poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blend was studied by long-term exposure to ambient conditions (27–30°C) in the laboratory. While the unplasticized blend showed obvious changes in physical properties such as hardening, loss of elasticity and embrittlement, the plasticized blend retained its properties. Thermo-oxidative ageing studies were carried out by evaluating the mechanical properties before and after ageing in an air oven at 80°C for 168 h. The relatively rapid degradation of PVC/ENR blend has been attributed to the high concentration of epoxy groups and the occurrence of ring-opening reactions to form ether crosslinks. It was found that the plasticizer confers adequate stabilization upon the addition of a certain threshold amount. The optimum amount of plasticizer required to adequately stabilize the blend is 20 phr. Above this there is a tendency for plasticizer migration to occur. The use of an antioxidant in conjunction with the plasticizer further stabilizes the blend. The general trend is of decrease in mechanical and physical properties with increase in DOP concentration. In addition, ease of processing also increases as indicated by the torque maxima and minima obtained from the Brabender plastograms.     

Mechanical and thermo-oxidative properties of blends of poly(vinyl chloride) with epoxidized natural rubber and acrylonitrile butadiene rubber in the presence of an antioxidant and a base

Being polar and compatible with poly(vinyl chloride), epoxidized natural rubber (ENR) is similar in behaviour to acrylonitrile butadiene rubber (NBR). To assess the extent of this similarity, the mechanical properties of 50/50 blends of PVC with these two rubbers were compared. Their response to thermo-oxidative ageing in the presence of an antioxidant and a base was also investigated by ageing the blends at 100°C for 7 days. Studies involving mechanical properties and FTIR were used to evaluate the extent of thermal degradation. The results revealed that blends of ENR show mechanical properties which are as good as, and in some instances better than, those of the NBR blends. However, the ENR blends with PVC are very prone to oxidative ageing. This might be attributed to the susceptibility of the oxirane group to ring-opening reactions, particularly in the presence of PVC, which yields HCl as it degrades. The amine-type antioxidant 2,24-trimethyl-1,2-dihydroquinoline (TMQ) improved the oxidative stability of both blends. This was more significant in the ENR blend, which in some cases attained stability comparable with that of NBR. The addition of a base, calcium stearate [Ca(St)₂], did not show any influence in the PVC/ENR blend, even though it was expected to curb acid-catalysed degradation. Ca(St)₂, however, improved the oxidative stability of the PVC/NBR blend. The combination of optimum amounts of TMQ and Ca(St)₂ effectively improved the tensile strength of both unaged blends, without appreciable adverse effect on elongation at break. This combination also imparted stability better than that of TMQ alone.     

The effect of epoxide content on compatibility of poly(lactic acid)/epoxidized natural rubber blends

The objective of this work was to determine the effect of the epoxide content in epoxidized natural rubber (ENR) on the miscibility and compatibility with poly(lactic acid) (PLA) in prepared PLA/ENR blends. PLA was blended with 10 wt% of ENRs (epoxidized at 10, 15, 20, and 25 mol%). The presented study showed that the in situ graft copolymer, PLA-g-ENR, was formed during melt blending in the blends containing 10 and 15 mol% ENR. This work is the initial study showing the presence of PLA-g-ENR in the blends by ¹H-NMR and ¹³C-NMR. PLA-g-ENR acted as a compatibilizer, producing a partially miscible blend, indicated by an inward shift of the α-transition temperatures of PLA and ENR in the blends. PLA-g-ENR also greatly reduced the particle size of ENR and increased the impact strength, tensile strength, and elongation at break of the blends. The epoxide content of ENR changed deformation mechanisms of the blends.     

The Effect of Epoxidized Sunflower Oil on the Miscibility of Plasticized PVC/NBR Blends

Blends of plasticized poly(vinyl chloride) (PVC) with several ratios of nitrile rubber (NBR) were studied. The effects of epoxidized sunflower oil (ESO) in combination with di-(2-ethylhexyl)phthalate (DEHP) in the PVC blends on the tensile strength, elongation, hardness, and dynamical mechanical analysis (DMA) were studied. The modulus and hardness results revealed that the addition of ESO to the blend favors the miscibility of PVC and NBR. The PVC/NBR/(DEHP-ESO) blends behave as a compatible system as is evident from the single T _g observed in DMA. The moderate level broadening of the T _g zone in blends is due to the presence of ESO in the plasticizer system. Blends of plasticized PVC and nitrile rubber showed promising properties. The ESO is suitable to partially replace DEHP in PVC/NBR blends.     

Properties of poly(vinyl chloride) incorporated with a novel soybean oil based secondary plasticizer containing a flame retardant group

A novel bio‐based plasticizer containing flame retardant groups based on soybean oil (SOPE) was synthesized from epoxidized soybean oil (ESO) and diethyl phosphate through a ring‐opening reaction. PVC blends plasticized with ESO and SOPE were prepared, respectively. Properties including rheological behavior, thermal stability, flame retardant performance, mechanical properties of PVC plasticized with ESO and SOPE were carefully studied. The results showed that the plasticized PVC blends indicated better compatibility, thermal, and mechanical properties. As a novel bio‐based plasticizer containing flame retardant groups, the TGA data indicated that the thermal degradation temperature of PVC blends plasticized with SOPE could reach to 275.5°C. LOI tests and SEM indicated that the LOI value of PVC blends could increase from 24.2 to 33.6%, the flame retardant performance of SOPE was put into effect by promoting polymer carbonization and forming a consolidated and thick flame retardant coating quickly, which is effective to prohibit the heat flux and air incursion. The enhancement in flame retardancy will expand the application range of PVC materials plasticized with SOPE. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42111.     

Mechanical and rheological properties of epoxidized soybean oil plasticized poly(lactic acid)

Poly(lactic acid) (PLA) is a well known biodegradable thermoplastic with excellent mechanical properties that is a product from renewable resources. However, the brittleness of PLA limits its general applications. Using epoxidized soybean oil (ESO) as a novel plasticizer of poly(lactic acid), the composite blend with the twin‐screw plastic extruder at five concentrations, 3, 6, 9, 12, and 15 wt %, respectively. Compared with pure PLA, all sets of blends show certain improvement of toughness to different extents. The concentration with 9 wt % ESO increases the elongation at break about 63%. The melt flow rates of these blends with respect to different ESO ratio have been examined using a melt flow indexer. Rheological behaviors about shear viscosity and melt strength analysis are discussed based on capillary rheology measurements. The tensile strength and melt strength of the blends with 6 wt % ESO simultaneity reach the maximums; whereas the elongation at break of the blends is the second highest level. ESO exhibits positive effect on both the elongation at break and melt strength. The results indicate that the blend obtained better rheological performance and melt strength. The content of 6 wt % ESO in PLA has been considered as a better balance of performance. The results have also demonstrated that there is a certain correlation between the performance in mechanical properties and melt rheological characterization for the PLA/ESO blends.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Contact angle behaviour of poly(vinyl chloride)/ epoxidized natural rubber miscible blends

—Contact angle studies of miscible poly(vinyl chloride)/epoxidized natural rubber (PVC/ ENR) blends were carried out in air using water and methylene iodide. The solid surface free energy was calculated from harmonic mean equations. Blending of PVC and ENR decreased their contact angle or increased their solid surface free energy due to the improved chain mobility, and the accumulation of excess polar sites at the surface through conformational alterations resulting from the specific interaction of PVC and ENR. The work of adhesion, interfacial free energy, spreading coefficient, and Girifalco-Good's interaction parameter changed markedly with the blend composition. In blends, PVC and ENR improved hydrophilicity, and wettability with polar and non-polar liquids. The presence of a plasticizer in PVC, in general, further improved the wettability and hydrophilicity in blends.     

Synthesis and application of an environmental epoxy plasticizer with phthalate-like structure based on tung oil and cardanol for poly(vinyl chloride)

An epoxidized cardanol tungoleate (ECT) based on tung oil and cardanol was synthesized through esterification and epoxidation. The chemical structure of the compound was verified by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹H-NMR). The plasticizing effects of ECT as the main plasticizer in poly(vinyl chloride) (PVC) was studied and compared with the commercial plasticizer dioctyl phthalate (DOP). The thermal migration stabilities, the thermal degradation process and the mechanical properties of PVC samples and the plasticization mechanism of ECT for PVC were investigated through the use of volatility, extraction, discoloration, and tensile tests as well as thermal gravity analysis (TGA), TGA–FTIR analysis, electronic universal testing machine and dynamic mechanical analysis (DMA). Compared with DOP, the ECT plasticized PVC can exhibits better thermal stability, more excellent tensile strength (17.28 MPa) and higher stretchability (629.41%), which is 1161% higher than DOP (1.37 MPa) plasticized PVC film. In addition, the migration resistance and volatility stability of ECT are much better than DOP. Therefore, this fully bio-based plasticizer based on tung oil and cardanol is a promising alternative plasticizer for PVC and may be an excellent phthalate substitute from the perspective of human health and sustainable development.     

Migration of additives in simulated landfills and soil burial degradation of plasticized PVC

Commercial sunflower oil was epoxidized, and epoxidized sunflower oil (ESO) was used as a thermal stabilizer for polyvinyl chloride (PVC). Semirigid and plasticized formulations stabilized with ESO were realized. Three plasticizers were used: dioctyle phthalate (DOP), diisodecycle phthalate (DIDP), and diisononyle adipate (DINA). Leaching tests simulating real landfill conditions were performed. The two model leachates selected for laboratory leaching tests were solution of acetic acid and distilled water, respectively, corresponding to simulants for domestic waste leachates and rainfall on wastes deposited in bulk. The leaching tests were carried out at 25 and 50°C during 15 days. The variation of the mass of the samples was followed as a function of time. On the other hand, the ageing of the PVC samples was investigated in a landfill soil for 6 months. The modifications of the structure of the polymer were followed by Fourier transform infrared spectroscopy (FTIR). Furthermore, the variation of density and mechanical properties (tensile and shore D hardness) were considered. The results showed that both nature and content of plasticizer influence the migration of the PVC additives used. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Aspects of miscibility in poly(vinyl chloride)/epoxidized natural rubber blends. Part I: Mechanical and morphological properties

Miscibility in poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blends was studied by examining evidence from tensile, impact, and physical properties. The observation of synergism in tensile strength, percent elongation at break, hardness, and relative density has reaffirmed PVC/ENR blends as miscible systems. Studies of impact properties, however, revealed that the blends are microheterogeneous in nature. This could be attributed to the large sizes of polymer molecules involved and the microgel content of ENR-50. Results from Fourier transform infrared spectroscopy (FTIR) revealed that hydrogen bonding is extensively involved in PVC/ENR systems. This evidence unveiled the exact nature of the specific interactions responsible for miscibility and hence the enhanced mechanical properties of PVC/ENR blends.     

Migration of Epoxidized Sunflower Oil and Dioctyl Phthalate from Rigid and Plasticized Poly(vinyl chloride)

The aim of this paper is the determination of the specific migration of epoxidized sunflower oil (ESO) from rigid and plasticized poly(vinyl chloride) (PVC) into food simulants. ESO was obtained by epoxidation of commercial sunflower oil and used as a thermal organic co-stabilizer for PVC. For that purpose, rigid and plasticized (0, 15, 30, and 45 wt% of dioctyl phthalate or DOP) PVC films stabilized with ESO in the presence of Zn and Ca stearates were used to perform migration testing in olive oil. The test conditions were 12 d at 20 and 40°C and 2 h at 70°C with and without agitation.

The determination of ESO migration was carried out by gas chromatography-mass spectrometry (GC-MS). ESO was quantified by an external standard addition method, using linoleic acid (C_18:2) as the external standard. The influence of various parameters, such as the agitation and time of contact, the temperature, the presence or the absence of the plasticizer, and the plasticizer concentration, was considered.     

聚乳酸/环氧大豆油共混物的性能

聚乳酸（PLA）与环氧大豆油（ESO）经熔融共混制得具有高韧性的PLA/ESO共混物,并研究了ESO含量对PLA微观形态、力学和流变性能的影响规律。结果表明：ESO可显著降低PLA的熔体黏度,提高PLA的韧性;PLA/ESO共混物在低ESO含量（10%）时为部分相容,而在高ESO含量（20%和30%）时发生了相分离,从而使共混物的断裂伸长率和冲击强度随ESO含量增加先增大后减小,且分别在ESO含量为20%和15%时达到最大值,约为PLA的17倍和2.9倍,而拉伸强度则随之减小。     

Effect of different curing systems on heat shrinkability and mechanical properties of ethylene vinyl acetate/epoxidized natural rubber blends

Ethylene vinyl acetate (EVA)/epoxidized natural rubber (ENR) blends containing 10 and 30 wt % ENR were prepared by using an internal mixer. Five different types of curing systems were employed: dicumyl peroxide (DCP), sulfur (S), phenolic resin (Ph), DCP + S, and DCP + Ph. DCP could crosslink with both EVA and ENR while S and Ph were curing agents for ENR. The DCP system provided the lowest tensile properties and tear strength because of low crosslinking in ENR phase. Addition of sulfur or phenolic resin increased the mechanical properties due to a better vulcanization of the rubber phase. The mechanical properties of the blends decreased with increasing ENR content. The rubber particle size in the blends containing 30% ENR played a more important role in the mechanical properties than the blends containing 10% ENR. ENR particle size did not affect heat shrinkability of EVA and a well vulcanized rubber phase was not required for high heat shrinkage. Furthermore, heat shrinkage of the blends slightly changed as the ENR content increased for all curing systems. With regard to the mechanical properties and heat shrinkability, the most appropriate curing system was DCP + Ph and in the case the 10 wt % ENR content produced a more favorable blend. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Thermal and mechanical properties of electron beam irradiated poly(vinyl chloride)/polystyrene blends

The effect of electron beam irradiation on the thermal and mechanical properties of poly(vinyl chloride)/polystyrene (PVC/PS) blends and PVC/PS blends containing epoxidized natural rubber (ENR) was studied. The thermogravimetric analysis study showed that the thermal decomposition of the plasticized PVC individual polymer goes through two stages, whereas PS decomposes through one stage. However, the temperature of the maximum rate of reaction (T_max) of PS is much higher than that for PVC and their blends. Meanwhile, the T_max was found to increase with increasing PS ratios in the blend. The thermal stability of PVC/PS blends was greatly increased after electron beam irradiation in comparison with unirradiated blends. Moreover, the addition of ENR to PVC/PS increased the thermal stability. On the other hand, the mechanical properties in terms of tensile strength and elongation at break of PVC/PS blends are lower than pure PVC polymer because of the immiscibility. However, the addition of ENR to the PVC/PS (80/20) blend increased the elongation at break from 114 to 321% associated with a small effect on the tensile properties. These behaviors were supported by structure morphology studies observations, which indicate an improvement in the interfacial adhesion between the phases. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers     

一种新型蓖麻油酸季戊四醇酯的制备及应用

用季戊四醇和蓖麻油酸通过酯化反应反应制备了蓖麻油季戊四醇酯。采用红外光谱仪和核磁共振仪对制备的产品的化学结构进行表征。并将其作为增塑剂与聚氯乙烯（PVC）共混,研究了塑化PVC的平衡扭矩、热性能和力学性能,对该增塑剂在不同溶媒中的耐迁移性进行了研究,并与邻苯二甲酸二辛酯和环氧大豆油的塑化性能进行了对比。结果表明,蓖麻油季戊四醇酯塑化PVC的加工平衡扭矩为14.9 N·m,改善了PVC的加工稳定性;塑化PVC的拉伸强度为23.28 MPa,断裂伸长率为263.13 %,耐迁移性能较邻苯二甲酸酯和环氧豆油较好,可以作为PVC增塑剂使用。     

Application of Poly(butylenes 2-methylsuccinate) as Migration Resistant Plasticizer for Poly(vinyl chloride)

The bio-based and biodegradable polyester poly(butylenes 2-methylsuccinate) (PBM) was successfully used as a polymeric plasticizer to modify poly(vinyl chloride) (PVC) in this work. The tensile properties, plasticization efficiency estimated by the lowered glass transition temperature and the enhanced elongation at break of the PVC/PBM blends and the migration stability of the PBM were investigated. It was indicated that the migration-resistant property of PVC plasticized with PBM was greatly superior to that with dioctyl phthalate (DOP). Furthermore, the tensile properties were comparable to that of PVC/DOP, indicating that the environmentally friendly PBM can be used as an alternative plasticizer to remove the potential health risks from migrating phthalates during applications.     

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

Epoxy 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.