@article { author = {Mohajerani, E. and Rezvani, M.H. and Mahzoon, R.}, title = {Improved Laser Induced Birefringence in Highly Doped Optical Polymers}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {179-284}, year = {2013}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2013.639}, abstract = {Application of polymers in novel and advanced scientific technologies is increasingly expanding. In this regard, optical polymers among different materials have found a special and unique position. A novel dye doped polymer thin film was prepared by taking advantage of dye molecules' interaction with the host environment. This sample, like self-assembled structures, makes use of this interaction to increase the response intensity significantly, and thus improve the performance of photonic devices. This highly improved response is mainly due to the possibility of making highly concentrated dye doped polymeric samples. In this way, the function of optical polymers in photonic applications and its mechanism were studied. Laser induced birefringence and spectral measurements were used in these studies. Time dependencies of the sample were studied and no significant qualitative differences were observed. It was shown that highly doped samples perform their function qualitatively correct in nonlinear optical applications. Also, in comparison with the best international reports published in this field so far, a significant improvement in final results has been observedquantitatively. Overall, according to extensive spectral changes and markable induced birefringence, this method is known as an effective way to construct improved photonic devices.}, keywords = {polymer thin film,nonlinear organic dye,intermolecular interaction,highly doped polymer devices,laser induced birefringence}, title_fa = {بهبود دوشکستی القایی لیزری در پلیمرهای نوری بسیار دوپه شده}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_639.html}, eprint = {http://jips.ippi.ac.ir/article_639_943787ec05988ad7fadd17bcfbe4e013.pdf} } @article { author = {Shiva, M. and Atashi, H.}, title = {Improvement in Tear Resistance and Crack Growth of Tire Tread Compound with Effective Cure Systems and Use of Semi-Reinforcement Fillers}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {285-295}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.743}, abstract = {Effect of partial natural rubber replaced with synthetic rubbers, styrene butadiene and cis butadiene, on failure and strength properties of bias tread NR/BR based compound was studied by efficient and conventional sulfur curing systems and mixtures of different carbon black grades. It was observed that failure behavior comprising tear resistance and crack growth in substituted compounds dropped significantly without any change in formulation. The type and crosslinking density were further studied with changes in sulfur/accelerator dosage and ratio. It was observed that tear resistance and crack growth improved with lowering sulfur/accelerator ratio, maintaining the same crosslink density,without any change in hysteresis. Other physico-mechanical properties of substituted NR/BR/SBR compound showed similar behavior as reference compound. The carbon black blends in NR/BR substituted compounds showed that using semi-reinforcing filler instead of the original reinforcing filler could improve crack growth resistance. Therefore, it is possible to decrease NR/BR ratio with modification of curing system and use of N330/N660 filler blends.}, keywords = {tear resistance,crack growth,efficient cure,conventional cure,chunking}, title_fa = {بهبود مقاومت پارگی و رشد ترک آمیزه رویه تایر با سامانه های پخت موثر و استفاده از پرکننده های نیمه تقویت کننده}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_743.html}, eprint = {http://jips.ippi.ac.ir/article_743_76475c498749e46ae28a7404e04b5bd9.pdf} } @article { author = {Montazar, M. and Jolaei, M.}, title = {Structure Modification of Polyester 3-Deminsional Fabrics with β-Cyclodextrin and Citric Acid}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {297-305}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.744}, abstract = {Modifying polyester spacer fabric by β-cyclodextrin produces a new product with outstanding characteristics. Citric acid is used as a crosslinking agent for improvement of durability of this material in textile fabrics. In this research different concentrations of citric acid and β-cyclodextrin were applied on a 3D fabric and some properties including weight change, weight of moisture residue, water absorption time, chromic ion and reactive dye absorptions were studied. Furthermore, the morphology of fabric surface has been examined by SEM and its chemical structure has been elucidated by FT-IR. The washing durability of the modified product has been also studied after 10 washing cycles. The results show that increasing the concentration of citric acid and β-cyclodextrin leads to higher stability of the modified fabrics.}, keywords = {citric acid,β-cyclodextrin,Polyester,host-guest system,fiber}, title_fa = {اصلاح ساختار پارچه پلی استر سه بعدی دوجداره با بتاسیکلودکسترین و سیتریک اسید}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_744.html}, eprint = {http://jips.ippi.ac.ir/article_744_b4fdebcf7f7d081bbc2e591b2424c49b.pdf} } @article { author = {Dabirian, F. and Hosseini Ravandi, S.A.}, title = {Production and Some Characteristics of Bulk Nanofibers Layers by Manipulation of Electrospinning System}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {307-313}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.745}, abstract = {The main purpose of this study is to introduce a new method for nanofibers by bulk layer production. In the present method the effect of some parameters including take-up velocity, applied voltage, polymer solution concentration on density of produced layers is investigated. The compression characteristic of nanofiber layers produced under optimum electrospinning is also investigated. It was shown that the layer density decreased by increasing polymer solution density while an increase in applied voltage and take-up velocity increased layer density. The lightest layer with density of 0.000374215 g/cm3 with 99/98% porosity are produced by this method at 15% polymer solution concentration with take-up velocity equal to 4.24 m/min and 8 kV voltages.}, keywords = {nanofiber,electrospinning,two nozzle,bulk,polyacrylonitrile}, title_fa = {تولید لایه های حجیم نانوالیاف با اعمال تغییراتی در روش الکتروریسی و بررسی برخی از مشخصه های آنها}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_745.html}, eprint = {http://jips.ippi.ac.ir/article_745_44bbc19fd1257f7c1f3ab82fb9ec0743.pdf} } @article { author = {Sadighi, M. and Darushi, S.}, title = {An Experimental Study on Impact Behavior of Fiber/Metal Laminates}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {315-327}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.746}, abstract = {During the last decades a new class of materials named fiber/metal laminates (FMLs) was introduced. It is a hybrid composite consisting of alternating thin layers of metal sheets and fiber-reinforced composite material. FMLs have both low weight and good mechanical properties. In this study, the impact behavior of this attractive material is investigated. The effect of fiber angle, stacking sequence and capacity of test apparatus were examined. In addition specimens have been prepared in two sizes according to two standards of ASTM D256-93a for plastics and then ASTM E23- 01 for metals. Test results show that suitable layering, using more aluminum layers and fiber sheets with zero angle in laminates improve the impact strength. The amount of energy absorption in heavy apparatus is higher than the light apparatus.}, keywords = {fiber-metal laminates,impact,fiber angle,glass fiber,stacking sequence}, title_fa = {بررسی تجربی خواص ضربه ای چندلایه ای های فلز ـ الیاف}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_746.html}, eprint = {http://jips.ippi.ac.ir/article_746_68e0721484103c1564aeda8200b2f72c.pdf} } @article { author = {Shokrieh, M.M. and Atashipour, S.R.}, title = {Resin Flow in Fiber Preformed by Vacuum Assisted Resin Transfer Molding with Flexible Tools}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {329-338}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.747}, abstract = {Vacuum assisted resin transfer molding, as a sub-branch of RTM is a method of manufacturing composite specimens. Considering the industrial development of this method, different modified techniques are designed to improve its performance. Among these techniques, using a half flexible mold is regarded as an important method. In this work, dominant equations of resin flow through the mold in polar coordinates are solved analytically. Based on this approach, closed-form solutions have been presented for different parameters such as thickness variation of preformed fiber, resin pressure, resin velocity and fiber volume fraction as functions of two variables, namely, time and the distance from injection port. After verification of the approach employed in this work, the results are presented. Important parameters influencing the quality and the rate production are studied in detail.}, keywords = {polymer composite,vacuum assisted resin transfer molding,flexible tool,preformed fibers,processing}, title_fa = {جریان رزین داخل الیاف پیش شکل داده شده در فرایند قالب گیری انتقالی رزین به کمک خلاء با ابزارهای انعطاف پذیر}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_747.html}, eprint = {http://jips.ippi.ac.ir/article_747_e827eed331ca1a801742179173c165e9.pdf} } @article { author = {Ahmadi, M. and Abbasi, F. and Gharebaghi Tazehkand, H.}, title = {Effect of Carbon Black/Organoclay Hybrid Filler System on Tire Tread Compound Properties}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {339-346}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.748}, abstract = {The enhanced dispersion of organophilic layered silicates improves the mechanical properties of polymer/ silicate composites. In this work, a hybrid filler system consisting of Cloisite 15A organoclay (OC) and carbon black (CB) was used to improve the properties of the tire tread compounds. The physical and mechanical properties of compounds were assessed by measurement of their cure properties, tensile, crack growth resistance and abrasion tests. The dispersion of organoclay layers was investigated by XRD analysis and transmission electron microscopy. The results have indicated that increases in tensile strength, elongation-at-break and rupture resistance were obtained by replacement of 5 phr CB with OC. However, increases in modulus and abrasion resistance were obtained by replacement of 3 phr CB with OC. Therefore replacement of 3 phr CB with OC was an optimum formulation for tread compound. The results have also indicated that with changing the mixing conditions to enhance the dispersion of clay layers, the mechanical and abrasion properties have improved. The XRD patterns and transmission electron micrographs have revealed that the distances between the layers are increased from 5.5 nm to 13.5 nm.}, keywords = {tire tread,organoclay,carbon black,morphology,abrasion}, title_fa = {بررسی اثر سامانه پرکننده هیبریدی دوده- خاک رس اصلاح شده بر خواص آمیزه رویه تایر}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_748.html}, eprint = {http://jips.ippi.ac.ir/article_748_8d86edc3136157d02c7266081f2a58ee.pdf} } @article { author = {Ghasemi, A.R. and Shokrieh, M.M.}, title = {Development of an Integral Method for Determination of Non-uniform Residual Stresses in Laminated Composites}, journal = {Iranian Journal of Polymer Science and Technology}, volume = {21}, number = {4}, pages = {347-355}, year = {2008}, publisher = {}, issn = {10163255}, eissn = {20080883}, doi = {10.22063/jipst.2008.749}, abstract = {A new method for determination of residual stresses in the bottom layers of laminated composites is developed. In this method the residual stresses are determined by performing a consecutive drilling of laminated composites in the center of the rosette and recording the strains after drilling each layer. The depth of the hole in each step is equal to the thickness of each layer and the maximum depth of driling is equal to the diameter of the hole. The integral method has been used for determination of the residual stresses because these stresses are distributed non-uniformly through the thickness of each layer. A computer program for simulation and calculation of the calibration factors of the incremental hole drilling process of laminated composites is presented. The calibration factors correlate the released strains to the residual stresses in each layer. The released strains in the incremental hole drilling process are divided in two parts. The first part is due to the released strain by increasing the holes depth and changing the geometry of the hole. The second part is due to the released strain from each layer by drilling the same layer. In this method, by calculating the calibration factors using the integration method and performing a finite element method, the residual stresses in each layer of laminated composites are calculated.}, keywords = {integral method,residual stresses,laminated composite,calibration factors,hole drilling}, title_fa = {توسعه روش انتگرال برای تعیین تنش های پس ماند غیریکنواخت در چندلایه های کامپوزیتی}, abstract_fa = {}, keywords_fa = {}, url = {http://jips.ippi.ac.ir/article_749.html}, eprint = {http://jips.ippi.ac.ir/article_749_bd9441570924bc63d15d9bfeda4c0466.pdf} }