Linear Low Density Polyethylene Blends Research Articles

Self-nucleation (SN) and successive self-nucleation and annealing (SSA) as powerful tools to determine the composition of polyolefin post-consumer recycled blends

For the incorporation of post-consumer recycled (PCR) resins in mechanical recycling processes, it is crucial to determine their composition accurately. The blends of linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) in PCR film resins pose a challenge due to their varying ratios. This study introduces a quantitative method that employs the successive self-nucleation and annealing (SSA) technique to analyze commercial PCR LLDPE/LDPE blend compositions. Our method is an efficient way to assess these blend compositions, offering an improved analysis compared with traditional methods. We established a series of calibration curves based on the SSA final melting trace to validate our approach. The SSA technique's efficacy was compared with the robust NMR method, showing that SSA can predict LLDPE contents in the blends with comparable accuracy. We demonstrate that the SSA methodology is an accurate and reliable technique for assessing complex waste streams, thereby facilitating the optimization of recycling processes and advancing the goals of sustainable materials management.

Simultaneous Effect of EBR on LLDPE and PDMS Rubber Blends and Its Nanocomposites for Cable Applications.

The impact of electron beam radiation on the blend of linear low-density polyethylene (LLDPE) and polydimethylsiloxane (PDMS) rubber at different doses from 50 to 300 kGy has been investigated. The irradiated sheets were examined for their morphology, gel content, thermal stability, melt behavior, and electrical and dielectric properties. The radiation treatment has reduced both the melting point and crystallinity of base polymers and their blends because of chain scission. As observed, 100 kGy doses of irradiated blend and 3 wt % of loaded nanosilica composite showed comparatively good thermal stability. The phase morphology of the LLDPE: PDMS rubber blend showed a honeycomb-like design before irradiation because of two-stage morphology, which prominently changed into a solitary stage after electron beam irradiation. This is because of intermolecular cross-link arrangement inside the singular parts, just like cross-linking development at the interface. From the AQFESEM study, it is observed that the stacking of nanosilica particles within the blend matrix is greatly reduced after electron beam irradiation. The addition of nanosilica within the blend increased the electrical conductivity and dielectric permittivity. The dielectric breakdown strength has been observed to be the highest for 3 wt % loaded nanocomposite and its irradiated sample. The result indicates that the nanocomposite can be utilized for high-voltage cable applications in indoor and outdoor fields.

Morphologies, structures, and properties on blends of triblock copolymers and linear low-density polyethylene

Abstract Focusing on the study of the phase separation behavior of triblock copolymer and linear low-density polyethylene (LLDPE) systems helps to understand the influence of microstructure on the properties of poly(vinylcyclohexane)-b- poly(ethylene)-b-poly(vinylcyclohexane) (PVCH-PE-PVCH/LLDPE) blends. We prepared a series of blends of LLDPE and PVCH-PE-PVCH and explained their compatibility from the microstructure. The research findings indicate that despite having similar block compositions, PVCH-PE-PVCH with a higher molecular weight exhibits significantly stronger phase separation and crystallization ability compared to PVCH-PE-PVCH with lower molecular weight. In PVCH-PE-PVCH/LLDPE blends, the addition of 10 %, 20 %, and 30 % LLDPE induces earlier crystallization and crystal phase separation of polyethylene (PE) fragments. In addition, compared to the lower molecular weight of PVCH-PE-PVCH, the higher molecular weight of PVCH-PE-PVCH exhibits a higher tendency for independent crystallization and shows significant crystal phase separation during the cooling crystallization process when blended with LLDPE. The PE segments in the lower molecular weight of PVCH-PE-PVCH can more easily enter the nanoscale domain of LLDPE. Impact fracture electron microscopy also reveals better compatibility between the lower molecular weight of PVCH-PE-PVCH and LLDPE compared to the higher molecular weight of PVCH-PE-PVCH. Furthermore, the blends of lower molecular weight of PVCH-PE-PVCH and LLDPE exhibit a greater growth rate in elongation at break.

Thermal and Rheological Properties of Fischer–Tropsch Wax/High‐Flow LLDPE Blends

AbstractWaxes find use as processing aids in filled compounds and polyethylene‐based masterbatches. In such applications, the thermal and physical property changes they impart to the polymer matrix are important. Therefore, this study details results obtained for blends prepared by mixing a Fischer–Tropsch (F–T) wax with a high‐flow linear low‐density polyethylene (LLDPE). The melting and crystallization behavior are studied using hot‐stage polarized optical microscopy (POM) and differential scanning calorimetry (DSC). The calorimetry results are consistent with partial cocrystallization of the two components. The melting and crystallization exo‐ and endotherms for the wax‐ and LLDPE‐rich phases remained separate. However, they change in shape and shift toward higher‐ and lower temperature ranges, respectively. It is found that increasing the wax content delays the crystallization, decreases the overall crystallinity, and reduces the size of the crystallites of the polyethylene‐rich phase. Rotational viscosity is measured at 170 °C in the Newtonian shear‐rate range. The variation of the zero‐shear viscosity with blend composition is consistent with the assumption of a homogeneous melt in which the chains are in an entangled state. Therefore, it is concluded that the wax and LLDPE are, in effect, miscible in the melt and partially compatible in the solid state.

Rheology modifier additive for enhanced processability of polyethylene forblown‐Filmapplications

AbstractPolyethylene is a versatile polymer suitable for a large variety of flexible and rigid packaging applications. Its mechanical and rheological properties can be tuned across a wide range by controlling its molecular architecture, such as the amount and distribution of olefinic comonomers (short chain branching), long chain branching, and molecular weight distribution. Linear low‐density polyethylene (LLDPE) is known for its high toughness which enables downgauged film structures and low‐density polyethylene (LDPE) is known for its excellent shear thinning and melt strength which enables enhanced processability and high throughput, such as on blown film lines. In order to obtain a balance of toughness and processability on films produced on blown film lines, blends of LLDPE and LDPE are commonly used. In this paper, we describe additive‐based approaches, including a new product, DOWLEX™ (TM = trademark of the Dow Chemical Company (“Dow”) or an affiliated company of Dow) GM AX01, which enhances melt strength and other rheological properties of polyethylene, enabling fabrication of films with lower LDPE content while still maintaining excellent rheological properties and higher toughness versus conventional LLDPE/LDPE blends. The higher toughness enables downgauging without loss of mechanical properties, which in turn reduces consumption of polymer resulting in a more sustainable solution.

Development and Characterization of LLDPE Blends with Different UHMWPE Concentrations Obtained by Hot Pressing.

To modify its characteristics, expand its applicability, and, in some cases, its processability, new blends using ultra-high-molecular-weight polyethylene (UHMWPE) have been developed. In this study, three different formulations of linear low-density polyethylene (LLDPE) and UHMWPE blends were prepared with 15, 30, and 45% (% w/w) UHMWPE in the LLDPE matrix. All mixtures were prepared by hot pressing and were immersed in water for one hour afterwards at a controlled temperature of 90 °C to relieve the internal stresses that developed during the forming process. The thermal characterization showed that the blends showed endothermic peaks with different melting temperatures, which may be the result of co-crystallization without mixing between the polymers during the forming process. The mechanical characteristics presented are typical of a ductile material, but with the increase in the percentage of UHMWPE, there was a decrease in the ductility of the blends, as the elongation at rupture of the blends was higher than that of the pure components. The morphologies observed by SEM indicate that there were two phases in the blends. This is the result of the system’s immiscibility due to the mode of preparation of the blends, wherein the two polymers may not have mixed intimately, confirming the results found with the thermal analyses.

Influence of carbon structures on the properties and photodegradation of LDPE/LLDPE films

AbstractThe effect of different carbon structures on the properties of low density polyethylene film and linear low density polyethylene blends (LDPE/LLDPE) subjected to artificial weathering, was studied. The carbon structures used were carbon black (CB), multi wall carbon nanotubes (MWCNT) and Graphene nanoparticles (GNP), at various loadings: 0.05, 0.1, 0.3, 0.5, 1.0, and 2 wt%. The PE‐Carbon structure composite films were characterized by optical microscopy (MOP), Haze, visible light transmission, UV–visible, thermogravimetric analysis (TGA), melt flow determinations (MFI) and tensile properties. Weathering measurements were evaluated in a QUV panel chamber with UV fluorescent lamps. The films degradation was analyzed following the change in carbonyl index of FTIR spectra, mechanical properties, and molecular weight. A noticeable better dispersion of CB and CNT particles in polyethylene matrix was observed compared with GNP. MWCNTs and CB produced high Haze and low visible light transmission. Thermal stability measured by TGA increased with the presence of GNP and CB. The crystallinity, melting, and crystallinity temperature (Tm and Tc) of the polymers increased with MWCNT and GNP. All the films with carbon structures presented an increase in the modulus of elasticity, with CB giving the highest elastic modulus. Artificial weathering of films with carbon structures showed that CB particles and CNT provided the highest UV protection to polyethylene, with a noticeable increase in low molecular weights and a retention in tensile strength and elongation at break which was reflected in maintaining their flexibility. Films with CNT showed the least significant changes in their properties, being more resistant to photo‐degradation.

Morphology and permeability of bio-based poly(butylene adipate-co-terephthalate) (PBAT), poly(butylene succinate) (PBS) and linear low-density polyethylene (LLDPE) blend films control shelf-life of packaged bread

Poly(butylene adipate-co-terephthalate) (PBAT), poly(butylene succinate) (PBS) and linear low-density polyethylene (LLDPE) were blended to produce bio-based packaging via blown-film extrusion. Blend ratios modified morphology, crystallinity and relaxation temperatures (T α ) of the films. Binary mixtures caused phase separation and non-homogeneous fibrous microstructures of immiscible polymers. Bio-based blend films containing LLDPE (LLDPE/PBAT and LLDPE/PBS) gave less homogeneous structures than PBAT/PBS films. The formation of oriented fibrous networks subsequently controlled mechanical and barrier properties of the blend films. LLDPE blending modified C=O carbonyl groups in PBAT and PBS, forming voids in topographic images indicating incompatibility. PBAT and PBS blends showed good compatibility and adhesion of polymer interface, causing smooth and compact structures with minimal surface roughness. Incorporation of PBAT and PBS sharply reduced crystallinity of LLDPE/PBAT and LLDPE/PBS films. LLDPE/PBAT blends had lower T α than neat PBAT and LLDPE, while T α of PBAT/PBS blends proportionally decreased at increasing PBS which indicated diverse polymer miscibility and molecular mobility. Water vapor permeability (WVP) and oxygen permeability (OP) fitted with polynomial and exponential equations, respectively and depended on blend ratios. Films containing higher PBS had combined higher WVP and lower OP, delaying fungal growth in packaged bread due to dehydration. Ratios of PBAT, PBS and LLDPE blend films clearly affected mold growth and crumb hardness during storage. Regardless of film components, the firmness of bread crumbs increased linearly with package WVP. Conversely, mold growth had insignificant correlation with OP. Moisture loss from bread crumbs due to high WVP showed dominant effects on microbial growth. Blending PBAT and PBS modified the morphology and permeability of bio-based films and increased the shelf-life of packaged bread. • Systematic investigations for packaging properties in bio-based PBAT/PBS/PE blends. • FTIR intensity ratios effectively monitor bonding and morphology modifications. • H 2 O and O 2 permeability in PBAT/PBS/PE blends fitted to cubic and exponential model. • Hardness of packaged bread linearly increased with water vapor permeability. • Water vapor permeability majorly affected mold growth and increasing crumb hardness.

Catalytic co-pyrolysis of wet-torrefied bamboo sawdust and plastic over the zeolite HY: Synergism and kinetics

In this study, the catalytic co-pyrolysis (CCP) of wet-torrefied bamboo sawdust (TB) and linear low-density polyethylene (LLDPE) over zeolites was carried out using the thermogravimetric analyzer. The analysis was carried out at four different heating rates (5–40 °C min−1) and under an inert (Ar) atmosphere. Four degradation stages were observed in the CCP of TB and LLDPE blends, the first stage being moisture removal. The peak decomposition temperature of catalytic pyrolysis (CP) of LLDPE over FAU was reduced by 251 °C as compared to that over HZSM-5 and the enhancement can be attributed to the topology of HY. The activation energies were calculated using isoconversional models: Kissinger–Akahira–Sunose model (KAS), Ozawa–Flynn–Wall model (OFW), and Friedman model (FM). The average activation energies (Eα) of the blends TBL3:1, TBL1:1, and TBL1:3 (TBL: Blend of torrefied biomass and LLDPE) were 171, 128, and 117 kJ mol−1, respectively, using the KAS model. The Eα of the blends was much lower as compared to that of TB, indicating a clear synergism. A multistep mechanism was observed in both CP of individual samples and CCP of blends, as analyzed by Criado's master plot. For example, the CCP of TBL1:3 followed geometric (volume) contraction (R3) and first-order reaction models at low and high conversions, respectively.

Manufacturing Pitch and Polyethylene Blends-Based Fibres as Potential Carbon Fibre Precursors.

The advantage of mesophase pitch-based carbon fibres is their high modulus, but pitch-based carbon fibres and precursors are very brittle. This paper reports the development of a unique manufacturing method using a blend of pitch and linear low-density polyethylene (LLDPE) from which it is possible to obtain precursors that are less brittle than neat pitch fibres. This study reports on the structure and properties of pitch and LLDPE blend precursors with LLDPE content ranging from 5 wt% to 20 wt%. Fibre microstructure was determined using scanning electron microscopy (SEM), which showed a two-phase region having distinct pitch fibre and LLDPE regions. Tensile testing of neat pitch fibres showed low strain to failure (brittle), but as the percentage of LLDPE was increased, the strain to failure and tensile strength both increased by a factor of more than 7. DSC characterisation of the melting/crystallization behaviour of LLDPE showed melting occurred around 120 °C to 124 °C, with crystallization between 99 °C and 103 °C. TGA measurements showed that for 5 wt%, 10 wt% LLDPE thermal stability was excellent to 800 °C. Blend pitch/LLDPE carbon fibres showed reduced brittleness combined with excellent thermal stability, and thus are a candidate as a potential precursor for pitch-based carbon fibre manufacturing.

Strategy for reducing molecular ensemble size for efficient rheological modeling of commercial polymers

We develop a method for efficient prediction of linear and nonlinear rheology of polydisperse polymers by judicious selection of a small number of representative polymer molecules from the large ensemble of chains comprising the molecular weight and branching distribution. Specifically, we use a numerical inversion of the double reptation model to select five or six representative molecular species to optimally fit the linear rheology of commercial polymers and then use the regressed parameters to compute the nonlinear rheology via the Rolie-double-poly (RDP) model. The method is tested for several model systems, namely, two polydisperse linear polystyrene (PS) samples described in Shivokhin et al. [Polym. Eng. Sci. 56, 1012–1020 (2016)] and Munstedt [J. Rheol. 24, 847–867 (1980)], a commercial linear low density polyethylene (LLDPE), and a low density polyethylene (LDPE) whose rheological properties are measured in the current study. For the linear polymers including the PS samples and the LLDPE, the predictions of the “representative” RDP model of the start-up extensional rheology are comparable to those of the “full” RDP model based on all the species drawn from the gas permeation chromatography characterization. The method then successfully predicts the linear rheology of blends of LLDPE and LDPE using the same representative molecules found by fitting each of the pure polymers. Further fitting the extensional rheology of the LDPE requires using the “priorities” q i and stretch relaxation times τ s , i of the representative molecules as adjustable parameters, whose values are then held fixed when predicting the extensional rheology of blends of the LDPE with the LLDPE roughly as successfully as does branch-on-branch model. The reduction in the number of representative polymer species offers new opportunities for faster simulations of flowing polymers, as well as for the prediction of segmental orientation to be used in the modeling of flow-induced crystallization.

Microstructural Contributions of Different Polyolefins to the Deformation Mechanisms of Their Binary Blends.

The mixing of polymers, even structurally similar polyolefins, inevitably leads to blend systems with a phase-separated morphology. Fundamentally understanding the changes in mechanical properties and occurring deformation mechanisms of these immiscible polymer blends, is important with respect to potential mechanical recycling. This work focuses on the behavior of binary blends of linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP) under tensile deformation and their related changes in crystallinity and morphology. All of these polymers plastically deform by shear yielding. When unmixed, the high crystalline polyolefins HDPE and PP both exhibit a progressive necking phenomenon. LDPE initiates a local neck before material failure, while LLDPE is characterized by a uniform deformation as well as clear strain hardening. LLDPE/LDPE and LLDPE/PP combinations both exhibit a clear-cut matrix switchover. Polymer blends LLDPE/LDPE, LDPE/HDPE, and LDPE/PP show transition forms with features of composing materials. Combining PP in an HDPE matrix causes a radical switch to brittle behavior.

Tailoring polypropylene for extrusion-based additive manufacturing

This paper reports on the optimization of polypropylene (PP) feedstock material towards extrusion-based additive manufacturing. To achieve this, two commercially available grades of polypropylene/ethylene random copolymers (raco PP) were modified, aiming to reduce warp deformation caused by shrinkage and at the same time reduce the anisotropic property by improving the interlayer bonding quality of 3D printed parts processed by fused filament fabrication (FFF). A β-nucleating agent, several amorphous polypropylenes (aPP) and one linear low-density polyethylene (LLDPE) were selected as additive or blending component with the goal to reduce shrinkage. The polypropylene feedstock material optimization was conducted by a combination of a lab-scale filament rod processing method and utilizing printed square tubes to optimize printing performance. The achieved results demonstrate that the crystallization behavior and E-modulus of polypropylene play significant roles for warp deformation in extrusion-based 3D printed parts. The β-nucleating agent alters the crystallization behavior, even a slightly negative influence on the warp deformation was observed. The investigated polymer blend of raco PP and LLDPE shows no significant contribution to reduce warpage and impairs also the interlayer bonding. The best results were achieved by blending raco PP with selected amorphous PPs. With two aPP grades warp deformation could be drastically reduced. In addition, the interlayer bonding quality is remarkably enhanced in these blends in spite of slight decreases in stiffness and strength. In conclusion, the optimized PP feedstock material features less warp deformation, high stiffness, and most importantly, outstanding interlayer bonding qualities.

English

English

Structure–Property–Process Relationship for Blown Films of Bimodal HDPE and Its LLDPE Blend

AbstractBlown films of bimodal‐high‐density polyethylene (HDPE) (BPE) and its blend containing 40 wt% of linear low‐density polyethylene (LLDPE) are prepared in various neck‐heights (NHs). The crystal structures of both films are investigated in detail using small‐angle X‐ray scattering and wide‐angle x‐ray diffraction techniques. The results show that the blending of LLDPE notably modifies the crystal structure of BPE, including crystal density (ρc), crystallite size of the 110 plane (〈L110〉), thickness of the lamellar crystal (Lc), and grain widths of the lamellae. The relationships between NH, crystal structure, and the resistance of dart‐drop impact (DDI) are investigated for both BPE and BPE/LLDPE films. The results indicate that the reorientation of lamellae might be a primary factor responsible for the DDI property. However, large values of ρc, Lc, and 〈L110〉 are required for the film to achieve high DDI.

Hollow Fiber Porous Nanocomposite Membranes Produced via Continuous Extrusion: Morphology and Gas Transport Properties.

In this work, hollow fiber porous nanocomposite membranes were successfully prepared by the incorporation of a porous nanoparticle (zeolite 5A) into a blend of linear low-density polyethylene (LLDPE)/low-density polyethylene (LDPE) combined with azodicarbonamide as a chemical blowing agent (CBA). Processing was performed via continuous extrusion using a twin-screw extruder coupled with a calendaring system. The process was firstly optimized in terms of extrusion and post-extrusion conditions, as well as formulation to obtain a good cellular structure (uniform cell size distribution and high cell density). Scanning electron microscopy (SEM) was used to determine the cellular structure as well as nanoparticle dispersion. Then, the samples were characterized in terms of mechanical and thermal stability via tensile tests and thermogravimetric analysis (TGA), as well as differential scanning calorimetry (DSC). The results showed that the zeolite nanoparticles were able to act as effective nucleating agents during the foaming process. However, the optimum nanoparticle content was strongly related to the foaming conditions. Finally, the membrane separation performances were investigated for different gases (CO2, CH4, N2, O2, and H2) showing that the incorporation of porous zeolite significantly improved the gas transport properties of semi-crystalline polyolefin membranes due to lower cell wall thickness (controlling permeability) and improved separation properties (controlling selectivity). These results show that mixed matrix membranes (MMMs) can be cost-effective, easy to process, and efficient in terms of processing rate, especially for the petroleum industry where H2/CH4 and H2/N2 separation/purification are important for hydrogen recovery.

Research and Manufacture of Stretch Films using LLDPE blends

New linear low-density polyethylene (LLDPE) blends were investigated to use as stretch and breathable films. In our investigation different types of LLDPE blends were prepared by extrusion. The characteristic melting and crystallization temperatures of these LLDPE blends were determined. Specimens were injection moulded and their tensile properties were measured. The LLDPE blends with the best thermal and mechanical results were chosen to prepare film by film blowing in laboratory conditions. Tearing properties of the films were also investigated. Our aim was to determine the most appropriate LLDPE blend for stretch film usable under industrial conditions.

The Usage of Recycled Material in Rotational Molding Process for Production of Septic Tank

Rotational molding is the forming process that use in produce large product, complexity product and hollow product with the limitation of process ability and material. Most of the rotational molding is a large product with a longer useful life compare to other technique, so to reused the material from other process can help to increase the competition of rotational molding in the market. This paper chooses recycled HDPE from blowing process due to it generally used by the market and not difficult to find. So in this paper choose to studies the blend of virgin LLDPE (linear low density polyethylene) and recycled HDPE (high density polyethylene) for application in septic tank by rotational molding process. Various ratio of blending were investigated to find the morphology, mechanical properties and the relation of melt flow rate and rheology. Mechanical properties are generally referred to tensile test, hardness test, impact strength and Morphology by Scanning Electron Microscope. Many studies have carried out to investigate about rotational molding forming process control, mold and process condition, some on material ability and new material to used in rotational molding to improve the mechanical properties and various technique in forming by rotational molding. But this article will investigated more about the use of recycled material from other forming technique process (which refer to blowing process in this article) to use in rotational molding process for produce septic tank compare to the commercial quality.

Non-isothermal degradation kinetics of virgin linear low density polyethylene (LLDPE) and biodegradable polymer blends

The thermal degradation kinetics of several polymers, including biodegradable blends were investigated in non-isothermal thermogravimetry using several analytical methods. Virgin linear low density polyethylene (LLDPE) and LLDPE blends with polystarch-N (PSN), a prodegradant starch additive material used in 20 and 40 wt%., were investigated to determine the degradation behaviour of such materials in pyrolysis conditions. The results were compared to those obtained with virgin low (LDPE) and high density polyethylene (HDPE). An analytical solution model was also developed to assess the two degradation steps of the biodegradable blends which enabled the assessment of the apparent activation energy (Ea) of each material in the blend on its own based on the initial and final degradation temperatures. It was observed that the thermal behaviour and Ea value didn’t change significantly with the increase of biodegradable prodegradant, which shows that biodegradable blends can be treated with similar conditions regardless of the content of the biodegradable masterbatch present in the blend.

Study and Characterization of LLDPE/Polyolefin Elastomer and LLDPE/EPDM Blend: Effect of Chlorinated Water on Blend Performance

The objective of this study was to investigate the effects of two elastomers, namely ethylene butene copolymer (EBC) and ethylene propylene diene monomer (EPDM), on the physical, thermal and morphological properties of blend after exposure to chlorine. Blends of linear low-density polyethylene (LLDPE), ethylene-butene copolymers (EBC) and ethylene propylene diene ter polymer (EPDM) with different content were prepared by melt mixing in a twin-screw extruder. The LLDPE blend with EBC and EPDM were tested with water containing 50 ppm and 5000 ppm chlorine under static condition for 500 hr at 25°C and 80°C. Highest weight gain was observed for a higher concentration of chlorine for LLDPE/EBC-55 and LLDPE/EPDM-37 blend. It is seen that at 50 ppm chlorine concentration, the mechanical properties of LLDPE, LLDPE/EBC blend and LLDPE/EPDM blend remain unchanged. Chemical changes in the aged sample were checked by Infrared spectroscopy (FTIR), where increase in the O-H and C=O infrared bands was observed. The thermal characteristics of LLDPE, LLDPE/EBC blend, and LLDPE/EPDM blends were investigated using DSC and TGA which shows melting temperature and crystalline melt temperature remains unchanged while percent crystallinity was increased by 10 percent for LLDPE. Scanning electron microscope (SEM) showed that there was no formation of the micro cracks and cavities of LLDPE/EBC 73 blend and LLDPE/EPDM 73 blend after exposure to a higher concentration of chlorine. It indicated the excellent stability of prepared blend against chlorinated water