Tailoring the crystalline structure of polypropylene parts molded through water‐assisted injection molding: Effects of melt temperature and polymeric nucleating agent

The melt temperature and a special polymeric nucleating agent [acrylonitrile–styrene copolymer (SAN)] were investigated to find an effective way for tailoring the crystalline structures of the water‐assisted injection‐molded polypropylene (WAIM PP) parts. The results showed that lowering the melt temperature led to the formation of a small amount of β‐form crystals in both outer and core layers of the WAIM PP parts. Nevertheless, the melt temperature had little effect on tailoring the crystalline structures of the WAIM PP parts. The addition of a low content (6 wt%) of the SAN was interestingly found to gradually influence the crystalline structures as lowering the melt temperature. WAIM PP/SAN blend parts with high contents of β‐form in both outer and core layers (30.7 and 18.4%, respectively), and high contents of transcrystals in the inner layer were molded at relatively low melt temperature (180°C), whereas the SAN had little influence on the crystalline structures at higher melt temperature (230°C). The formation of the transcrystals was ascribed to the in situ fibrillation of the SAN, which was resulted from high shear and cooling rates caused by high‐pressure water penetration during WAIM. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers     

Formation mechanism of crystal morphologies in LLDPE/HDPE blends investigated via water‐assisted and conventional injection molding

The LLDPE/HDPE blends with two different weight ratios as well as pure LLDPE were molded by means of water‐assisted and conventional injection molding (WAIM and CIM) in terms of their different thermal fields. The formation of the crystal morphology in the molded parts was investigated by a scanning electron microscope. The results showed that banded spherulites formed in the WAIM and CIM pure LLDPE parts. Banded spherulites of LLDPE coexisted with the randomly oriented lamellae of HDPE for LLDPE/HDPE blend parts with lower HDPE content at higher cooling rates, whereas a banding to nonbanding morphological transition occurred for LLDPE component (particularly for blend with higher HDPE content) at lower cooling rates. The heterogeneous nucleation effect of HDPE component on LLDPE component was responsible for the banding to nonbanding morphological transition by hindering the twist of LLDPE lamellae. It was interesting to find that the thermal effect, rather than the shear effect, was the main factor for the formation of crystal morphologies in both CIM and WAIM blend parts. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

A novel β‐nucleating agent for isotactic polypropylene

The nucleating ability of p‐cyclohexylamide carboxybenzene (β‐NA) towards isotactic polypropylene (iPP) was investigated by differential scanning calorimetry, X‐ray diffraction, polarized optical microscopy and scanning electron microscopy. β‐NA is identified to have dual nucleating ability for α‐iPP and β‐iPP under appropriate kinetic conditions. The formation of β‐iPP is dependent on the content of β‐NA. The content of β‐phase can reach as high as 96.96% with the addition of only 0.05 wt% β‐NA. Under non‐isothermal crystallization the content of β‐iPP increases with increasing cooling rate. The maximum β‐crystal content is obtained at a cooling rate of 40 °C min^–1. The supermolecular structure of the β‐iPP is identified as a leaf‐like transcrystalline structure with an ordered lamellae arrangement perpendicular to the special surface of β‐NA. Under isothermal crystallization β‐crystals can be formed in the temperature range 80–140 °C. The content of β‐crystals reaches its maximum value at a crystallization temperature of 130 °C. © 2012 Society of Chemical Industry     

Morphological distribution of polymeric nucleating agents in injection‐molded isotactic polypropylene plates and its influence on nucleating efficiency

The morphological development of a special polymeric nucleating agent [acrylonitrile–styrene copolymer (SAN)] in the isotactic polypropylene (iPP) matrix in the process of injection molding has been investigated by means of wide‐angle X‐ray diffraction and scanning electron microscope. The current experimental results indicate that the shear field, in combination with the temperature gradient, has great influence on the morphological distribution of SAN in the process of injection molding. For injection‐molded SAN/iPP specimens with higher SAN concentration (≥4%), SAN assembles to many microspheres and disperses uniformly in the isotropic core region; while from isotropic core region to oriented skin region, these SAN microspheres are gradually stretched into fibrils as a result of shear effect. On the contrary, for the specimens with lower SAN concentration (<4%), only microspheres can be observed in the core region and the skin region. At the same time, SAN has been proved to be a kind of special β‐nucleating agent. The addition of SAN into iPP helps enhances the crystallinity and the content of β crystal form of injection‐molded specimen. The morphology and the distribution of SAN in iPP matrix have great influence on the SAN's nucleating activity, which will ultimately affect the final crystalline structures of injection‐molded specimens. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Squeeze Flow-Induced Hierarchical Morphology in Microinjection Compression Molded Thin-Walled Plates of PP/SAN Blend and Its Nanocomposite with Halloysite Nanotubes

Thin-walled plates of polypropylene (PP), PP/acrylonitrile–styrene copolymer (SAN) blend,and PP/SAN/halloysite nanotubes (HNTs) blend nanocomposite were molded via microinjection-compression molding (μ-ICM). Hierarchical crystal morphologies were observed for the three plates. The SAN appeared mainly as microfibers in μ-ICM plates of PP/SAN blend and PP/SAN/HNTs blend nanocomposite, facilitating the formation of atranscrystals-dominated layer between shear and core layers in each of the two plates. Moreover, the SAN microfibers and HNTs synergetically increased the crystallinity of the PP. Tensile strength and microhardness of the PP plates were enhanced in the presence of SAN microfibers and HNTs.     

Effect of Melt‐Memory on the Crystal Polymorphism in Molded Isotactic Polypropylene

The influence of γ‐quinacridone as a β‐crystal nucleating agent in injection molded isotactic polypropylene (iPP) is discussed. Samples are injection molded and characterized via polarized‐light optical microscopy and X‐ray diffraction. Mold‐filling simulation is used to understand the shear and cooling processes during sample preparation. The cooling rate associated with the quench near the mold wall is estimated to be greater than 600 K s^?1 using simulation, confirming previous studies that β‐crystal growth is not supported at that cooling rate. The non‐nucleated samples form β‐crystals at a distance of 100–300 µm from the skin and in the core of the sample, which is not expected based on quiescent cooling data. Since the mold‐filling simulation does not predict shear in the core, the formation of the β‐crystals formed in this region is attributed to shear‐induced crystallization effects in the injection unit of the molding machine that are not modeled in flow simulation, as they are typically excluded from any molding simulation analysis. This “melt‐memory” effect has shown to be significant, and it is suggested that the prediction of final properties of injection moldings requires understanding and knowledge of the entire shear history of the material including that of the injection unit.     

Shear‐Induced Skin‐Core Structure of Molten Isotactic Polypropylene and the Formation of β‐Crystal

The study of crystallization behavior and crystalline morphology of polymer melt under shear flow is of great interest due to the strong effect of flow field on the final properties of polymer products in the practical processing. In this respect, the shearing hot stage provides a unique tool which monitors sensitively the changes in crystalline structure induced by precise experimental conditions. Herein, the impacts of both melting temperature and shear rate on the crystallization behavior of isotactic polypropylene (iPP) melt are investigated. Under static conditions, there are only random spherulite structures. Once shear is involved, the cylindrite‐layers appear near both surfaces of the sample, which is consistent with the skin‐core structure in the injection molded parts. Meanwhile, the β‐crystals can be developed and are related to the molecular orientation, depending on the applied melting temperatures and shear rates. More interestingly, the crystallinity of β‐crystal in the pure iPP can reach 15%. The above results indicate that the melting temperature and shear rate are important factors in determining the β‐form crystal development of iPP matrix.     

Morphologies and crystal structures of styrene–acrylonitrile/isotactic polypropylene ultrafine fibers fabricated by melt electrospinning

Ultrafine fibers or fiber web is an attractive material for its high aspect ratio or porous structure which is welcomed in various applications. In this study, ultrafine fibers (5–10 μm) of styrene–acrylonitrile (SAN) copolymer/isotactic polypropylene (iPP) blends were produced by melt electrospinning, SAN acted as a polymeric nucleating agent (PNA) in iPP fibers. Wide‐angle X‐ray diffraction, differential scanning calorimetry, scanning electron microscopy, and polarized optical microscopy were used to investigate the morphologies and the crystal structures of SAN/iPP electrospun fibers. The results showed that SAN/iPP melt formed microfibers with different morphologies and crystallinities through electrostatic stretching. The morphological distribution of SAN in iPP fibers depended on the SAN content, and the distribution influenced its nucleating activity and the final crystal structure of SAN/iPP electrospun fibers. After annealing treatment, the molecular chains of iPP in the confined SAN/iPP microfibers disorientated and rearranged, leading to the formation of a mixture of α‐ and γ‐crystal forms. The relative amount of the γ‐crystal form depended on PNA's concentration, annealing temperature and annealing time. Melt electrospun iPP fibers prepared in this study were collected as fiber webs that can be used for protective clothing material, filtration media, reinforcement for composites, and so on. POLYM. ENG. SCI., 53:2674–2682, 2013. © 2013 Society of Plastics Engineers     

Critical role of depressurization and effects of saturation conditions in the formation of β‐Crystal during isotactic polypropylene foaming with supercritical CO2

The melting behavior and crystalline forms of isotactic polypropylene (iPP) samples crystallized under different conditions of pressure and temperature were investigated using differential scanning calorimeter (DSC) and wide‐angle X‐ray diffraction (WAXD), respectively. When treated with dynamic supercritical CO₂(Sc‐CO₂), iPP samples undergo the formation of β‐crystal that does not occur on the treatment with atmospheric pressure and static supercritical CO₂(Sc‐CO₂) pressure. In addition, the relative content of β‐crystal has deep dependence on melt state and depressurization rate. Depressurization plays very critical role in the formation of β‐crystal by means of imposing three‐dimensional tensile field during cell growth. The tensile field induced α‐row nuclei where the formation of β‐crystal occurred. This finding will provide one new method to induce β‐crystal in iPP parts. POLYM. ENG. SCI. 56:980–986, 2016. © 2016 Society of Plastics Engineers     

Stretching‐induced β‐crystal of iPP: Influence of stretching ratio

The iPP sheet is extruded through a slit die, in which the extruding rate is set small enough to eliminate the shear stress as much as possible. Simultaneously, the extruded sheets were stretched with different stretching ratios (SR). With SR increasing from 1 to 6.67, fraction of β‐crystal increases dramatically from 1.5 to 13%, which indicates that SR is favorable to the occurrence of β‐crystal. However, as SR further increases, it gradually decreases to 0, which reveals that SR can steadily restrain the formation of β‐crystal. As the thickness of the sheets decreases with the increase of SR, higher cooling rate occurs for the sheets extruded at larger SR. When SR is in the range of 1–6.67, the cooling rate might probably fix the oriented chains and provide a proper thermal environment for subsequent growth of β‐crystal, thereby, fraction of β‐crystal increases. Growth of β‐crystal could be restricted by higher cooling rate, which leads to the gradual decrease of β‐crystal fraction with the further increase of SR. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Nonisothermal crystallization and melting behavior of β‐nucleated isotactic polypropylene and polyamide 66 blends

A highly novel nano‐CaCO₃ supported β‐nucleating agent was employed to prepare β‐nucleated isotactic polypropylene (iPP) blend with polyamide (PA) 66, β‐nucleated iPP/PA66 blend, as well as its compatibilized version with maleic anhydride grafted PP (PP‐g‐MA), maleic anhydride grafted polyethylene‐octene (POE‐g‐MA), and polyethylene‐vinyl acetate (EVA‐g‐MA), respectively. Nonisothermal crystallization behavior and melting characteristics of β‐nucleated iPP and its blends were investigated by differential scanning calorimeter and wide angle X‐ray diffraction. Experimental results indicated that the crystallization temperature (T) of PP shifts to high temperature in the non‐nucleated PP/PA66 blends because of the α‐nucleating effect of PA66. T of PP and the β‐crystal content (K_β) in β‐nucleated iPP/PA66 blends not only depended on the PA66 content, but also on the compatibilizer type. Addition of PP‐g‐MA and POE‐g‐MA into β‐nucleated iPP/PA66 blends increased the β‐crystal content; however, EVA‐g‐MA is not benefit for the formation of β‐crystal in the compatibilized β‐nucleated iPP/PA66 blend. It can be relative to the different interfacial interactions between PP and compatibilizers. The nonisothermal crystallization kinetics of PP in the blends was evaluated by Mo's method. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A highly active and selective β‐nucleating agent for isotactic polypropylene and crystallization behavior of β‐nucleated isotactic polypropylene under rapid cooling

Zinc adipate (Adi‐Zn) was observed to be a highly active and selective β‐nucleating agent for isotactic polypropylene (iPP). The effects of Adi‐Zn on the mechanical properties and the β‐crystals content of nucleated iPP were investigated. The impact strength of iPP nucleated with 0.2 wt % Adi‐Zn was 1.8 times higher than that of neat iPP. In addition, wide‐angle X‐ray diffraction analysis indicated that the content of β‐crystals in nucleated iPP (k_β value) reached 0.973 with 0.1 wt % Adi‐Zn, indicating that Adi‐Zn is a highly active and selective β‐nucleating agent for iPP. Furthermore, fast scanning chip calorimetry (FSC) studies using cooling rates from 60 to 13,800 °C min^?1 revealed that the formation of β‐crystals significantly depended on the cooling rates. At cooling rates below 3000 °C min^?1, only β‐crystals existed. However, at cooling rates above 6000 °C min^?1, β‐crystals failed to form. Moreover, a lower critical crystallization temperature that corresponded to the generation of β‐crystals was investigated using cooling‐induced crystallization, and the results are in good agreement with those of a previous study. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43767.     

Enhanced β‐crystal formation of isotactic polypropylene under the combined effects of acid‐corroded glass fiber and preshear

The acid‐corroded glass fiber (GF)/isotactic polypropylene (iPP) composite was injection molded by mixing–injection molding (MIM). Through this method, preshear can be imposed on melt during mix–plasticization process. The crystalline structure across the thickness direction of the injection‐molded bars was investigated by wide‐angle X‐ray diffraction and differential scanning calorimetry (DSC). It was unexpectedly found that, in core region, the acid‐corroded GF/iPP sample has the highest content of β‐form crystals, followed by uncorroded GF/iPP and neat iPP. Additionally, the crystalline morphology was investigated by polarized optical microscopy (POM) and scanning electron microscopy, and the results showed that β‐transcrystallization is preferably present in the acid‐corroded GF/iPP system. Confirmed by POM and DSC, the acid‐corroded GF shows strong β‐nucleation ability to iPP under static condition. Combined with the main features of MIM, three β‐nucleation origins in the acid‐corroded GF/iPP system under injection molding condition are proposed: (1) precursors induced by preshear in the barrel, (2) row‐nuclei induced by local shear, and (3) the acid‐corroded GF nuclei. POLYM. COMPOS. 34:1250–1260, 2013. © 2013 Society of Plastics Engineers     

Effect of oscillatory shear field on the morphology and mechanical properties of β‐nucleated isotactic polypropylene

The aim of this study is to investigate the effects of extra oscillatory shear field on morphology and mechanical properties of β‐nucleated isotactic polypropylene by using a homemade vibration‐assisted extrusion apparatus, in which oscillatory shear field was introduced into the extrusion head driven by crank and link mechanism. The results show that the extra oscillatory shear filed induces a significantly enhanced orientation of β‐crystal besides causing a better homogeneous dispersion of β‐nucleant, and the oriented β‐crystal has a high ratio of daughter lamellae to parent lamellae orientation, which was rarely reported in other literatures. The vibration increased the overall crystallinity and changed the relative content of β‐crystal. For the higher level nucleation agent content iPP(0.4 wt%), the relative contents of β‐crystal just changed a little or basically unchanged after vibration. However, for iPP contenting 0.2 wt% nucleation agent, the content of β‐crystal decreased. All the changes in the morphology, crystallinity, dispersion of β‐nucleant and β‐crystal content had a great influence on the mechanical properties, and that result was the improvement of yield stress and decrement of the elongation at break. POLYM. ENG. SCI., 57:838–845, 2017. © 2016 Society of Plastics Engineers     

Investigation on the morphology and tensile behavior of β‐nucleated isotactic polypropylene with different stereo‐defect distribution

Large amount of work has been published on the tacticity‐properties relationship of isotactic polypropylene (iPP). However, the stereo‐defect distribution dependence of morphology and mechanical properties of β‐nucleated iPP (β‐iPP) is still not clear. In this study, two different iPP resins (PP‐A and PP‐B) with similar average isotacticity but different uniformities of stereo‐defect distribution were selected, their β‐iPP injection molding specimens were prepared, and the morphology evolution and tensile behaviors were studied by means of differential scanning calorimetry (DSC), 2D wide‐angle X‐ray diffraction (2D‐WAXD) and scanning electron microscope (SEM). DSC results showed that with the same concentration of β‐nucleating agent (0.3 wt % WBG‐II), PP‐B with more uniform stereo‐defect distribution exhibited more amount of β‐phase than that of PP‐A with less uniform stereo‐defect distribution, indicating that PP‐B is more favorable for the formation of β‐phase. SEM results showed that PP‐B formed more amount of β‐crystals with relatively high structural perfection, while in PP‐A a mixed morphology of α‐ and β‐phase with obviously higher amount of structural imperfection emerges. The results of room‐temperature tensile test indicated that the yield peak width of PP‐B was obviously wider, and the elongation at break of PP‐B was higher than that of PP‐A, showing a better ductile of PP‐B. The morphology evolution results of SEM, 2D‐WAXD and DSC suggest that, a combination of lamellar deformation and amorphous deformation occurred in PP‐A, while only amorphous deformation mainly took place in PP‐B, which was thought to be the reason for the different tensile behaviors of the samples. In the production of β‐PP products via injection molding, the uniformity of stereo‐defect distribution was found to be an important factor. PP with more uniform distribution of stereo‐defect favors the formation of large amount of β‐phase with high perfection, which exhibit superior ductile property. The related mechanism was discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40027.     

Melt rheology of polypropylene reinforced with polyaniline‐coated short glass fibers

This research deals with the melt rheology of isotactic polypropylene (iPP) reinforced with short glass fibers (SGF) coated with electrically conductive polyaniline (PAn). Composites containing 10, 20, and 30 wt % PAn‐SGF were studied. Moreover, a composite of 30 wt % PAn‐SGF was also prepared with a blend of iPP and PP‐grafted‐maleic anhydride (iPP/PP‐gMA). The composites showed linear viscoelastic regime at small strain amplitudes. The onset of nonlinearity decreased as the concentration of filler increased. The time‐temperature superposition principle applied to all composites. The filler increased the shear moduli (G′, G″) and the complex viscosity η*. Steady‐state shear experiments showed yield stress for the composites with 20 and 30 wt % PAn‐SGF. Strikingly, the 10 wt % composite showed higher steady state viscosity than the 20 wt %. Rheo‐optics showed that shear induced disorder of microfibers at a concentration of 10 wt %. However, at 20 wt % concentration shear aligned the microfibers along the flow axis, this would explain the anomalous steady state viscosity values. The viscosity exhibited a shear thinning behavior at high shear rates for all composites. Creep experiments showed that the filler induced greater strain recovery in the composites and that the amount of strain recovery increased as the PAn‐SGF concentration increased. However, the enhancement of strain recovery (as well as shear viscosity) was more significant when using the iPP/PP‐gMA blend, suggesting greater adhesion between this matrix and the filler PAn‐SGF. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Influence of different β‐nucleating agent on crystallization behavior,morphology, and melting characteristic of multiwalled carbon nanotube‐filled isotactic polypropylene nanocomposites

To obtain isotactic polypropylene (iPP) nanocomposites with high β‐crystal content, TMB5, calcium pimelate and calcium pimelate supported on the surface of nano‐CaCO₃ were used as β‐nucleating agent and MWCNT filled β‐nucleated iPP nanocomposites were prepared. The effect of different β‐nucleating agent and MWCNT on the crystallization behavior and morphology, melting characteristic and β‐crystal content of β‐nucleated iPP nanocomposites were investigated by DSC, XRD and POM. The results indicated that addition of MWCNT increased the crystallization temperature of iPP and MWCNT filled iPP nanocomposites mainly formed α‐crystal. The β‐nucleating agent can induce the formation of β‐crystal in MWCNT filled iPP nanocomposites. The β‐nucleating ability and β‐crystal content in MWCNT filled β‐nucleated iPP nanocomposites decreased with increasing MWCNT content and increased with increasing β‐nucleating agent content due to the nucleation competition between MWCNT and β‐nucleating agents. It is found that the calcium pimelate supported on the surface of inorganic particles as β‐nucleating agent has stronger heterogeneous β‐nucleation than calcium pimelate and TMB5. The MWCNT filled iPP nanocomposites with high β‐crystal content can be obtained by supported β‐nucleating agent. POLYM. COMPOS., 36:635–643, 2015. © 2014 Society of Plastics Engineers     

Effect of nucleating duality on the formation of γ‐phase in a β‐nucleated isotactic polypropylene copolymer

BACKGROUND: It is a challenge for polymer processing to promote the formation of γ‐phase under atmospheric conditions in isotactic polypropylene (iPP) copolymer containing chain errors. Incorporation of an α‐nucleator in iPP copolymer seems reasonable since it can enhance non‐isothermal crystallization. Up to now, however, the issue regarding a β‐nucleated iPP copolymer still remains unclear, which is the subject of this study. RESULTS: The results indicate that the γ‐phase indeed occurs in a β‐nucleated random iPP copolymer with ethylene co‐unit (PPR) sample and becomes predominant at slow cooling rates (e.g. 1 °C min^?1) where the formation of the β‐form is suppressed to a large extent. With detailed morphological observations the formation of γ‐phase in the β‐nucleated PPR sample at slow cooling rate is unambiguously attributed to the nucleating duality of the β‐nucleator towards α‐ and β‐polymorphs. The α‐crystals, induced by the β‐nucleator, serve as seeds for the predominant growth of the γ‐phase. Moreover, the presence of the β‐nucleator, acting as heterogeneous nuclei, promotes the formation of γ‐phase in the nucleated PPR sample, at least to some extent. CONCLUSION: The findings in this study extend our insights into the formation of γ‐phase in β‐nucleated iPP copolymer and, most importantly, provide an alternative route to obtain iPP rich in γ‐phase. Copyright © 2008 Society of Chemical Industry     

On the differences in micro‐deformation mechanism between isotactic polypropylene and β‐nucleated isotactic polypropylene as revealed by the confocal laser scanning microscopy

To understand the toughness enhancement of β‐nucleated isotactic polypropylene (iPP) in comparison with iPP, the differences in the micro‐deformation mechanisms between the neat iPP and β‐nucleated iPP were visualized using the confocal laser scanning microscopy (CLSM). Structure of the α‐ and β‐spherulites situated close to the tip of the sharp starter crack has been investigated during tensile deformation in the viewing field of the CLSM. In the α‐spherulite of the neat iPP, highly localized inter‐ and intra‐spherulitic micro‐shear bands have been observed. In the β‐nucleated iPP, relatively uniform distribution of diffuse shear bands has been observed in the β‐phase, while the α‐phase remained relatively undeformed exhibiting only narrow intra‐spherulitic shear bands in the direction perpendicular to the loading direction. Delocalization of plastic deformation into diffuse shear bands in β‐nucleated iPP can explain its enhanced crack resistance compared with the neat iPP exhibiting highly localized shear banding. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

A novel highly efficient β‐nucleating agent for polypropylene using nano‐CaCO3 as a support

In order to increase the isotactic content of β‐nucleated polypropylene (β‐iPP) and decrease the cost of its production, the investigation and development of novel highly efficient β‐nucleators are important issues. Nano‐CaCO₃ was used as a support to prepare a supported β‐nucleator, nano‐CaCO₃‐supported calcium pimelate. Fourier transform infrared spectral analysis shows that an in situ chemical reaction takes place between nano‐CaCO₃ and pimelic acid. Differential scanning calorimetry results indicate that the crystallization and melting temperatures of β‐phase in supported β‐nucleator‐nucleated iPP are higher than those of calcium pimelate‐nucleated iPP. The β‐nucleating ability of the supported β‐nucleator is little influenced by the cooling rate and crystallization temperature over a wide range. The decreased content of pimelic acid in the supported β‐nucleator slightly decreases the crystallization temperature of iPP but it has no influence on the content of β‐phase in nucleated iPP. A novel supported β‐nucleator has been successfully synthesized via pimelic acid supported on the surface of CaCO₃. The crystallization temperature of iPP and melting temperature of β‐phase in iPP nucleated using the supported β‐nucleator are higher than those of iPP nucleated using calcium pimelate. The concept of a supported nucleator will provide a new way to increase the efficiency of polymer additives and to decrease the amounts of them that need to be used by using nanoparticles as supports. Copyright © 2010 Society of Chemical Industry