Polymerization Speed Research Articles

The influence of viscosity buildup on the foaming dynamics of rigid polyurethane foams

AbstractThe viscoelastic properties development during the reactive foaming of four standard polyurethane formulations was monitored using a flooded parallel plate rheometer. The measurements in situ demonstrated how foams of low catalyst content took longer than 10 min to increase their viscosity from 1 to 103 Pa s, while foams with higher catalysts reached this modulus in less than 4 min. This polymerization speed deeply impacted the evolution of the cellular structure during foaming, which was demonstrated through in situ x‐ray imaging and computer simulation. Foams with high catalyst stabilized in their final cell size in 4–5 min, concurring with the stage of largest viscosity buildup. In contrast, the foams of low catalyst content underwent strong degeneration as a result of the slow gelification and stiffening of the matrix. Simulation results also revealed that stabilization of the cellular structure happens faster when the catalyst and blowing agent contents are increased.

A Systematic Study on Biobased Epoxy-Alcohol Networks: Highlighting the Advantage of Step-Growth Polyaddition over Chain-Growth Cationic Photopolymerization.

Vanillyl alcohol has emerged as a widely used building block for the development of biobased monomers. More specifically, the cationic (photo-)polymerization of the respective diglycidyl ether (DGEVA) is known to produce materials of outstanding thermomechanical performance. Generally, chain transfer agents (CTAs) are of interest in cationic resins not only because they lead to more homogeneous polymer networks but also because they strikingly improve the polymerization speed. Herein, the aim is to compare the cationic chain-growth photopolymerization with the thermally initiated anionic step-growth polymerization, with and without the addition of CTAs. Indeed, CTAs lead to faster polymerization reactions as well as the formation of more homogeneous networks, especially in the case of the thermal anionic step-growth polymerization. Resulting from curing above the TG of the respective anionic step-growth polymer, materials with outstanding tensile toughness (>5MJ cm-3) are obtained that result in the manufacture of potential shape-memory polymers.

Thiol-acrylate based polymer wall-stabilized cholesteric liquid crystal enables flexible bistable states light shutter

Bistable-states mode light shutter boost the applications in smart windows or transparent displays due to the significant energy efficiency. In this study, polymer wall-stabilized cholesteric liquid crystals (PWSCLC) with regular microstructures and outstanding electric field frequency-controlled bistability were prepared using non-liquid crystalline thiol-acrylate monomers system and polymerization under a photomask. The addition and proportion of the thiol monomer played an essential role in the morphology structures of the polymer network. Thanks to the effectively modulation of polymerization speed, periodic regular polymer wall morphology was obtained, which improved the transmittance and the long-term stability. Under a suitable voltage, repeatedly reversible switch between transparent and scattering states was successfully realized via frequency regulation, and both states remained stable for more than 10 days after removing electric field. Remarkably, the mechanical strength of the PSWCLC film was significantly improved due to the relatively high polymer concentration, proving feasibility for the flexible applications and large-scale preparation.

Effect of Ligand Steric Hindrance on Catalytic Polymerization of Cycloolefin Polymer (COP)

AbstractThe traditional two‐component Ziegler‐Natta catalyst has low catalytic activity when initiating ring‐opening metathesis polymerization (ROMP) and is unstable and easy to generate polymerization gels. Therefore, it is necessary to add a third group of ligands with appropriate steric hindrance to improve the catalytic activity of the catalyst. The effects of ligands′ steric hindrance and other reaction conditions on the catalytic activity of tungsten hexachloride (WCl6) as catalyst and aluminum triethyl (AlEt3) as co‐catalyst were investigated. The results showed that the size of the ligands′ steric hindrance affected the catalytic activity of ROMP, and the small steric hindrance caused the polymerization rate to be too fast, which was easy to produce gels, and when the steric hindrance of the ligands was too large, its solubility was not good, which was not conducive to the normal polymerization. When stearyl alcohol was selected as the ligand, the highest catalytic activity was 3123 mol cycloolefin polymer (COP)/mol W, and the reaction speed of polymerization was also the fastest and the complete transformation only needed 30 min when the ligand/W was 25. It was found that the polymerization reaction was stable without gels and the obtained polymer molecular weight was appropriate, 17.8 kDa, under the conditions of Al/W=80, reaction temperature 60 °C, monomer concentration 10 w/v %, catalyst/monomer 5*10−4 : 1, chain transfer agent/monomer 0.005 : 1.

Regulating copolymer architecture using photoiniferter polymerization to direct composite morphology

Due to mild conditions and straightforward synthetic routes, photoiniferter polymerization has received increasing use as a facile method for preparation of polymers with highly controlled structure. However, low quantum yields inherent to thiocarbonylthio species result in polymerization speeds that are considerably slower than traditional controlled radical polymerization techniques. To improve polymerization speed while maintaining high level control, it is critical to understand relationships between reaction parameters and ultimate polymer structure. In this work, initiating light intensity, reactant concentration, and monomer pendant groups were manipulated in the photoiniferter polymerization of acrylate monomers to explore the effect of these conditions on reaction kinetics and molecular weight control. Polymerization rate of n-butyl acrylate was significantly enhanced by increasing light intensity rivaling speeds of conventional thermally initiated RAFT polymerization while enabling more precise control over molecular weight. Interestingly, photoiniferter rate asymptotically approached saturation at relatively high light intensities. Moreover, degradation of trithiocarbonate species occurred at greater intensities, ultimately resulting in moderate increases in molecular weight. Increased reactant concentration enabled faster rates with bulk polymerization, possibly due to reduced macro radical mobility and termination. Additionally, comparing photoiniferter polymerization of methyl acrylate and hydroxyethyl acrylate showed that greater polarity considerably enhanced polymerization speeds. Finally, the utility of precisely controlling polymer structure was demonstrated by synthesizing and incorporating a series of amphiphilic block copolymers with increasing molecular weight into a photocurable epoxy resin. The well-defined block copolymer structures enabled controllable phase separation and thermomechanical properties in epoxy composites. This work showed that photoiniferter polymerization speeds could be significantly enhanced using elementary reaction conditions, and that these conditions enable facile production of well-defined copolymers allowing tailored composite morphology and properties.

Elongator stabilizes microtubules to control central spindle asymmetry and polarized trafficking of cell fate determinants.

Asymmetric cell division gives rise to two daughter cells that inherit different determinants, thereby acquiring different fates. Polarized trafficking of endosomes containing fate determinants recently emerged as an evolutionarily conserved feature of asymmetric cell division to enhance the robustness of asymmetric cell fate determination in flies, fish and mammals. In particular, polarized sorting of signalling endosomes by an asymmetric central spindle contributes to asymmetric cell division in Drosophila melanogaster. However, how central spindle asymmetry arises remains elusive. Here we identify a moonlighting function of the Elongator complex-an established protein acetylase and tRNA methylase involved in the fidelity of protein translation-as a key factor for central spindle asymmetry. Elongator controls spindle asymmetry by stabilizing microtubules differentially on the anterior side of the central spindle. Accordingly, lowering the activity of Elongator on the anterior side using nanobodies mistargets endosomes to the wrong cell. Molecularly, Elongator regulates microtubule dynamics independently of its acetylation and methylation enzymatic activities. Instead, Elongator directly binds to microtubules and increases their polymerization speed while decreasing their catastrophe frequency. Our data establish a non-canonical role of Elongator at the core of cytoskeleton polarity and asymmetric signalling.

Effects of Hemodilution on Clot Waveform Analysis Parameters, Clotting Factors, and Thrombin Generation Assays in a Dilutional Model Based on Analysis of 11 Healthy Male Blood Donors.

BackgroundClot wave analysis (CWA) during activated partial thromboplastin time (aPTT) measures the speed and extent of fibrin polymerization in the plasma. This study aimed to evaluate the effects of hemodilution on CWA parameter, clotting factors, and thrombin generation assays in a dilutional model.Material/MethodsPlatelet-poor plasma obtained from 11 healthy male volunteers was diluted with 0.9% sodium chloride by 10–80% to analyze coagulation profiles, CWA, clotting factors, and thrombin generation assays. CWA includes 5 parameters: the time-dependent variable (aPTT), rate/acceleration (min1, min2, and max2), and magnitude of signal change (delta).ResultsCritically low activities of 30% for clotting factors and 100 mg/dl of fibrinogen were determined at dilutions of 70% and 60%, respectively. Peak thrombin and endogenous thrombin potential were significantly lower compared with baseline after 50% and 80% dilution, respectively. aPTT did not correlate with the decrease in the clotting factors up to dilutions of 50% and subsequently became abnormal values. As the change in rate/acceleration parameters parallels the time course of clotting factor activity in a dilution-dependent linear manner, these parameters indicate an intervention threshold at critically low activities of clotting factors. The strongest correlations were observed between clotting factors and aPTT, clotting factors and min2, delta and peak thrombin (r=0.95), and delta and fibrinogen (r=0.98).ConclusionsaPTT was significantly correlated with clotting factors, while the rate/acceleration parameters and delta changed with variation in thrombin and fibrinogen generation. These findings may help in evaluating coagulability.

Preparation and characterization of porous and stable sodium- and potassium-based alkali activated material (AAM)

The aim of this work is to produce highly porous and stable alkali-activated material (AAM) prepared from two combinations of sodium (Na)- and potassium (K)-based alkali solutions (NaOH/Na2SiO3 and KOH/K2SiO3). The reactive metakaolin as precursor and AAM were characterized using X-ray diffraction spectroscopy (XRD), X-ray fluorescence spectroscopy (XRF), aluminum nuclear magnetic resonance spectroscopy (27Al MS-NMR), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), field emission scanning electron microscopy (FESEM), compressive strength measurement and Brunauer–Emmett–Teller (BET) surface analysis. The porosity of the AAMs were increased by using hydrogen peroxide and sodium percarbonate as foaming agents. Characterization results showed the viscosity of the K-AAM paste was 70% lower than that of the Na-AAM paste. However, the volume of the Na-AAM paste in an air-tight plastic tube was three times higher than that of K-AAM, but the specific surface area (SSA) of K-AAM were 30% higher than those of Na-AAM. In terms of compressive strength, the blank AAM (foaming agent-free) demonstrated the highest strength values: 6.1 MPa for K-AAM and 9.0 MPa for Na-AAM. When the concentration of the foaming agent was increased, the compressive strength of both the materials decreased but were still around 1.0 MPa. The FESEM images of the Na-AAM and K-AAM produced with H2O2 indicated the high porosity of materials which were also observed in SSA values of AAM. Furthermore, the XRD data showed that the Na-AAM contained water in hydrate form (halloysite) compared with the K-AAM, suggesting the different polymerization reaction route and speed between these AAM.

SYNTHESIS AND PHOTOCHEMICAL PROPERTIES OF NEW STYRYLQUINOLINE-CONTAINING POLYMERS

Compounds 1a, 1b and 5c, 5d were obtained by Knoevenagel condensation with the corresponding aromatic aldehydes during 14 hours. The new methacrylic monomers with styrylquinoline containing moiety were synthesized by reaction the alcohols with methacryloyl chloride. Polymers were synthesized by free radical polymerization. Polymerization ability was investigated and kinetic parameters were determined for compounds 2a, 2b and 6c, 6d during thermoinitiated homopolyme­rization. Polymerization was carried out for 10% solutions of monomers in DMF at 80 °C in argon atmosphere with 1% AIBN. Polymers were characterized by 1HNMR spectroscopy. The speed of polymerization of all new mono­mers was higher than for MMA and phenyl methacrylate due to the effect of the substi­tuent in the p-position of the aromatic ring of the styrylquinoline fragment. In addition, the speed of polymerization increased due to the donor effect of the substituent. It was established that the speed of polymerization for 2b is higher than for monomer 2a. It is possible that decrease in the speed of polymerization occurs due to the substituent, which exhibits electron-accepting properties and can be a trap for free radicals. The results of photochemical and optical activities of the corresponding po­lymers are presented. Investigations of the absorption spectra of the synthesized polymers prove that the optically active styrylquinoline fragment in the polymers is preserved. Thus the photochemical properties of the new po­lymers will correspond to the properties of styrylquinoline-containing compounds. It was established that the introduction of electron-donating groups in the styrylquinoline fragment leads to a bathochromic shift of the absorption spectrum. Changes in absorption maxima during UV irradiation of compound 3a demonstrate photoinduced trans-cis isomerization. From the obtained and presented results, it can be concluded that polymers with styrylquinoline and iminostyrylquinoline fragments can be considered as promising materials for creating materials based on them that require photosensitivity in a certain range of wavelengths.

Context-dependent DNA polymerization effects can masquerade as DNA modification signals

BackgroundSingle molecule measurements of DNA polymerization kinetics provide a sensitive means to detect both secondary structures in DNA and deviations from primary chemical structure as a result of modified bases. In one approach to such analysis, deviations can be inferred by monitoring the behavior of DNA polymerase using single-molecule, real-time sequencing with zero-mode waveguide. This approach uses a Single Molecule Real Time (SMRT)-sequencing measurement of time between fluorescence pulse signals from consecutive nucleosides incorporated during DNA replication, called the interpulse duration (IPD).ResultsIn this paper we present an analysis of loci with high IPDs in two genomes, a bacterial genome (E. coli) and a eukaryotic genome (C. elegans). To distinguish the potential effects of DNA modification on DNA polymerization speed, we paired an analysis of native genomic DNA with whole-genome amplified (WGA) material in which DNA modifications were effectively removed. Adenine modification sites for E. coli are known and we observed the expected IPD shifts at these sites in the native but not WGA samples. For C. elegans, such differences were not observed. Instead, we found a number of novel sequence contexts where IPDs were raised relative to the average IPDs for each of the four nucleotides, but for which the raised IPD was present in both native and WGA samples.ConclusionThe latter results argue strongly against DNA modification as the underlying driver for high IPD segments for C. elegans, and provide a framework for separating effects of DNA modification from context-dependent DNA polymerase kinetic patterns inherent in underlying DNA sequence for a complex eukaryotic genome.

Heterogeneous photosensitizers: Super-efficient dual functional polydopamine nanohybrid for epoxy photopolymerization

The photosensitivity of nanoparticulate polydopamine (PDA) and polydopamine coated multiwalled carbon nanotubes (PDA/MWCNT) and their effect on the photopolymerization of epoxy monomers were systematically investigated. PDA/MWCNT nanohybrid at only 0.625 wt% has been shown to photo-catalyse the polymerization speed and conversion when compared with the commercial free radical photoinitiator, BAPO or non-free radical enhanced cationic photoinitiating resin systems. More importantly, it substantially increased the conversion by more than 140% over the unfilled free radical promoted cationic photoinitiating resin system. Covalent coated PDA/MWCNT nanohybrids were fabricated by oxidative polymerization of dopamine on the surface of acid treated MWCNTs. The modified MWCNT nanofiller has a dual role as photosensitizer/co-initiator in the FRPCP photoinitiating system and as mechanical reinforcement for the epoxy matrix. The use of PDA nanoparticles also led to the improvement in the polymerization process, albeit a limited one. Further evaluation of the observation suggests that the increase in the polymerization speed could be due to the photoinduced electron transfer effect in the polydopamine domain of the hybrid. The super efficiency effect has been explained through the heterojunction formation at the interface of dissimilar semi-conductive/conductive materials, polydopamine, a bio conjugated molecule with UV sensitivity and MWCNT hybrids, in the curing of epoxy monomers. This type of hybridized sensitizers/co-initiators have the potential to be applied in vat type 3D printing technologies such as SLA and DLP enabling printing with light blocking additives which otherwise pose a challenge in UV–Vis enabled curing and printing.

Preparation of Hollow-Porous Rosin-Based Polyurethane Microspheres with pH-Responsive Characteristics

Preparation of polymer microspheres from naturally occurring resource is a challenge. Here, a rosin-based polyol (RAG) was used to prepare polyurethane resin (RPU) firstly, and then act as both self-assembled precursor and emulsifier, rosin based polyurethane microspheres (RPUMs) were prepared. In the process of self-emulsification, the RPU formed vesicles by self-assembly. The outer shell of the vesicle consisted of hydrophilic segments, while the inner shell contained the hydrophobic phase. After cross-linking the RPU and removal of the solvent in the core, the porous-hollow microspheres with pH-sensitive were obtained. The microspheres were characterized by optical microscope (OM), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The effect of type and amount of the hydrophilic chain extender, and solvent on the morphology, particle size and distribution, and buffer volume of the microspheres were determined. The best conditions for synthetic RPUMs were as follows: nNCO/nOH = 1, nRAG:n1-(2-hydroxyethyl) piperazine = 4:6, with azodiisobutyronitrile level of 1.0 wt.%, based on reactive monomers, mixing speed of both emulsification and polymerization at 400 r·min−1, the RPUMs synthesized had porous-hollow structure with a buffer volume of 1.6 mL.

Frontally polymerizable shape memory polymer for 3D printing of free-standing structures

Four-dimensional (4D) printing is used to describe three-dimensional (3D)-printed objects with properties that change over time. Shape memory polymers (SMPs) are representative materials for 4D printing technologies. The ability to print geometrically complex, free-standing forms with SMPs is crucial for successful 4D printing. In this study, an SMP capable of frontal polymerization featuring exothermic self-propagation was synthesized by adding cyclooctene to a poly(dicyclopentadiene) network, resulting in switching segments. The rheological properties of this SMP were controlled by adjusting incubation time. A nozzle system was designed such that the SMP could be printed with simultaneous polymerization to yield a free-standing structure. The printing speed was set to 3 cm min−1 according to the frontal polymerization speed. A free-standing, hexagonal spiral was successfully printed and printed spiral structure showed excellent shape memory performance with a fixity ratio of about 98% and a recovery ratio of 100%, thereby demonstrating the 3D printability and shape memory performance of frontally polymerizable SMPs.

Spatiotemporal changes in microtubule dynamics during dendritic morphogenesis

ABSTRACT Dendritic morphogenesis requires dynamic microtubules (MTs) to form a coordinated cytoskeletal network during development. Dynamic MTs are characterized by their number, polarity and speed of polymerization. Previous studies described a correlation between anterograde MT growth and terminal branch extension in Drosophila dendritic arborization (da) neurons, suggesting a model that anterograde MT polymerization provides a driving force for dendritic branching. We recently found that the Ste20-like kinase Tao specifically regulates dendritic branching by controlling the number of dynamic MTs in a kinase activity-dependent fashion, without affecting MT polarity or speed. This finding raises the interesting question of how MT dynamics affects dendritic morphogenesis, and if Tao kinase activity is developmentally regulated to coordinate MT dynamics and dendritic morphogenesis. We explored the possible correlation between MT dynamics and dendritic morphogenesis together with the activity changes of Tao kinase in C1da and C4da neurons during larval development. Our data show that spatiotemporal changes in the number of dynamic MTs, but not polarity or polymerization speed, correlate with dendritic branching and Tao kinase activity. Our findings suggest that Tao kinase limits dendritic branching by controlling the abundance of dynamic MTs and we propose a novel model on how regulation of MT dynamics might influence dendritic morphogenesis.

Porous carbon derived from ZIF-8 modified molecularly imprinted electrochemical sensor for the detection of tert-butyl hydroquinone (TBHQ) in edible oil

In this manuscript, ZIF-8 derived nanoporous carbon material (ZC) was prepared and used as modification material to construct a molecularly imprinted electrochemical sensor for the direct detection of tert-butyl hydroquinone (TBHQ) in edible oil. Electrochemical characterizations, scanning electron microscopy and X-ray diffraction show that ZC has excellent conductivity, high electrochemical active area and stable porous framework structure. Using TBHQ as template and o-phenylenediamine as functional monomer, the sensor was constructed. Experimental parameters such as the number of polymerization cycle, polymerization speed, and pH of the measured solution, removal and rebinding time were studied. Under optimized conditions, the prepared sensor showed a wider linear range from 1.0 μmol L−1 to 75.0 μmol L−1 with the detection limit of 0.42 μmol L−1 (S/N = 3). Meanwhile, the sensor also expressed good selectivity, repeatability, reproducibility, stability and successfully applied for the determination of TBHQ in real edible oil, giving satisfactory results.

Alkali-metal hexamethyldisilazide initiated polymerization on alpha-amino acid N-substituted N-carboxyanhydrides for facile polypeptoid synthesis

Polypeptoids have been explored as mimics of polypeptides, owing to polypeptoids’ superior stability upon proteolysis. Polypeptoids can be synthesized from one-pot ring-opening polymerization of amino acid N-substituted N-carboxyanhydrides (NNCAs). However, the speed of polymerization of NNCAs can be very slow, especially for NNCAs bearing a bulky N-substitution group. This hindered the exploration on polypeptoids with more diverse structures and functions. Therefore, it is in great need to develop advanced strategies that can accelerate the polymerization on inactive NNCAs. Hereby, we report that lithium/sodium/potassium hexamethyldisilazide (Li/Na/KHMDS) initiates a substantially faster polymerization on NNCAs than do commonly used amine initiators, especially for NNCAs with bulky N-substitution group. This fast NNCA polymerization will increase the structure diversity and application of polypeptoids as synthetic mimics of polypeptides.

Studying the polymerization efficiency of photosensitive compositions by using the surface plasmon resonance method

In a real-time scale, it has been investigated the polymerization process in photosensitive compositions based on oligourethanacrylates with various concentrations of photoinitiators by using the method of surface plasmon resonance. Experimentally determined were the speed of polymerization and induction period for the studied samples of photopolymerization compositions as well as their optimum ratio of components for the chosen illumination wavelength 407 nm. It has been ascertained that with increasing the concentration of photoinitiators Irgacure 651 and Irgacure 819 from 1 up to 2% the speed of polymerization is increased by 3 and 7 times, respectively, while the induction period is decreased by almost 2 and 10 times, respectively. The presence of Irgacure 819 in these compositions provides the highest polymerization speed and the lowest induction period, which is related with the optimal choice of the illumination source wavelength inside the absorption spectrum of initiator, and the competitive absorption in other components of the photopolymer composition is minimal. These investigations are useful for developing optimal compositions of the studied materials for using them in various branches of industry.

A continuum model for the growth of dendritic actin networks

Polymerization of dendritic actin networks underlies important mechanical processes in cell biology such as the protrusion of lamellipodia, propulsion of growth cones in dendrites of neurons, intracellular transport of organelles and pathogens, among others. The forces required for these mechanical functions have been deduced from mechano-chemical models of actin polymerization; most models are focused on single growing filaments, and only a few address polymerization of filament networks through simulations. Here, we propose a continuum model of surface growth and filament nucleation to describe polymerization of dendritic actin networks. The model describes growth and elasticity in terms of macroscopic stresses, strains and filament density rather than focusing on individual filaments. The microscopic processes underlying polymerization are subsumed into kinetic laws characterizing the change of filament density and the propagation of growing surfaces. This continuum model can predict the evolution of actin networks in disparate experiments. A key conclusion of the analysis is that existing laws relating force to polymerization speed of single filaments cannot predict the response of growing networks. Therefore, a new kinetic law, consistent with the dissipation inequality, is proposed to capture the evolution of dendritic actin networks under different loading conditions. This model may be extended to other settings involving a more complex interplay between mechanical stresses and polymerization kinetics, such as the growth of networks of microtubules, collagen filaments, intermediate filaments and carbon nanotubes.

Coronin 2B regulates dendrite outgrowth by modulating actin dynamics.

Cytoskeletal remodeling is indispensable for the development and maintenance of neuronal structures and functions. However, the molecular machinery that controls the balance between actin polymerization and depolymerization during these processes is incompletely understood. Here, we report that coronin 2B, a conserved actin-binding protein, is concentrated at the tips of developing dendrites and that knockdown of coronin 2B inhibits the growth of dendrites. Importantly, coronin 2B interacts with actin and reduces the F-actin/G-actin ratio. Furthermore, the coiled-coil domain of coronin 2B is required for its oligomerization, thus confining coronin 2B to neurite tips. Our findings collectively suggest that coronin 2B is important for promoting dendrite outgrowth by limiting the speed of actin polymerization at growth cones.

Deformability of bamboo impregnated with thermosetting resin in upset forging

We developed a processing technique to apply plastic deformation to solid bamboo impregnated with thermosetting resin. To prevent the forming defects such as incomplete filling during upset forgings, we investigated the factors that affect the deformability of the bamboo. We conducted compression tests of the bamboo impregnated with phenol-formaldehyde resin using flat dies. The die temperature and the presence or absence of the lubricant were varied to change the thermal softening/hardening conditions of the impregnated bamboo and the friction characteristics between the bamboo and the dies, respectively. The compressed bamboo samples extended in a perpendicular direction to the bamboo fibers, and the extension ratio (Et) was higher when a lubricant was compared to that in a no-lubricant condition. The change in the Et with temperature was different between the without- and with- lubricant conditions. The results suggest that the friction on the dies significantly affects the deformability of the sample with no lubricant; however, the effect of friction was smaller than that of the flow stress of the bamboo, when the lubricant was used. The polymerization speed of the impregnated resin in the bamboo is also an important factor that affects the deformability of the samples, especially under low-friction conditions. To form a thin and large or complex shape product via flow forming, it is preferable to compress at a low temperature at which the impregnated resin does not polymerize with friction minimized.