scholarly journals The flame retardancy and rheological properties of PA6/MCA modified by DOPO-based chain extender

RSC Advances ◽  
2017 ◽  
Vol 7 (32) ◽  
pp. 19593-19603 ◽  
Author(s):  
Jianan Cai ◽  
Alvianto Wirasaputra ◽  
Yaming Zhu ◽  
Shumei Liu ◽  
Yubin Zhou ◽  
...  

Addition of DOPO-based chain extender (DEP) simultaneously enhanced the flame retardancy and mechanical properties of PA6/MCA through chain extension and coaction in flame-retarding.

RSC Advances ◽  
2015 ◽  
Vol 5 (40) ◽  
pp. 31878-31885 ◽  
Author(s):  
Alvianto Wirasaputra ◽  
Jianqing Zhao ◽  
Yaming Zhu ◽  
Shumei Liu ◽  
Yanchao Yuan

Figure melt torque of PA6 mixed with different contents of chain extender BGPPO. The addition of small molecule diepoxide (BGPPO) greatly enhanced the melt torque, rheological and mechanical properties of polyamide-6 through chain extension reaction.


2011 ◽  
Vol 284-286 ◽  
pp. 2384-2387
Author(s):  
Jin Cui Zhang ◽  
Xi Jun Liu ◽  
Tie Ning Ma

Polyurethane elastomers (PUE) were prepared by casting method using the prepolymer and the chain extender. In here, the prepolymer synthesized by using poly(tetramethylene glycol ether) (PTMG) and toluene diisocyanate (TDI), the chain extender was a mixture of 3,5-dimetylthio toluene diamine (E-300) and triethanolamine. The effects of the NCO concentration in prepolymer, the molar ratio of E-300/triethanolamine, and the chain extension coefficient of NCO/NH2 on the mechanical properties of the prepared PUE were studied. The results showed that the prepared PUE possesses excellent mechanical properties which can meet the drum scraper’s application requirements when the NCO concentration in prepolymer was 5.06% and the molar ratio of composite chain extender was 0.92/0.08.


Polymers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1218 ◽  
Author(s):  
Yodthong Baimark ◽  
Sumet Kittipoom

Stereocomplex polylactide (scPLA) films were prepared by melt blending of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) with and without an epoxy-based chain extender before compression molding. The obtained scPLA films were characterized through differential scanning calorimetry, X-ray diffractometry (XRD), tensile testing and dimensional stability to heat. XRD patterns revealed that all the scPLA films had only stereocomplex crystallites. The obtained results showed that the chain-extension reaction improved mechanical properties of the scPLA films, however, it suppressed stereocomplexation and heat resistance.


2021 ◽  
pp. 089270572110514
Author(s):  
Jing Sun ◽  
Anrong Huang ◽  
Shanshan Luo ◽  
Min Shi ◽  
Jiling Song ◽  
...  

Biodegradable poly(butylene adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA) composites were prepared by melt blending, and chain extender was used to improve the compatibility of PBAT/PLA blends through the chemical reaction. The influence of PLA and chain extender contents on mechanical properties, morphology, and rheological properties of PBAT/PLA composites was systematically investigated. The results revealed that the Young’s modulus and stress values gradually increased under the same strain, whereas the elongation at break decreased with the increase of chain extender content for PBAT/PLA (80/20) composites. Noteworthy, the presence of chain extender improves the interfacial compatibility between PLA and PBAT phases. At the chain extender content of 0.4, 0.6, and 0.8 wt.%, the extensional viscosity of the composites exhibited an increasing trend, whereas an obvious strain-hardening phenomenon emerged in the uniaxial extensional curves.


Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3531
Author(s):  
María Virginia Candal ◽  
Maryam Safari ◽  
Mercedes Fernández ◽  
Itziar Otaegi ◽  
Agurtzane Múgica ◽  
...  

The recyclability of opaque PET, which contains TiO2 nanoparticles, has not been as well-studied as that of transparent PET. The objective of this work is to recycle post-consumer opaque PET through reactive extrusion with Joncryl. The effect of the reactive extrusion process on the molecular structure and on the thermal/mechanical/rheological properties of recycling post-consumer opaque PET (r-PET) has been analyzed. A 1% w/w Joncryl addition caused a moderate increase in the molecular weight. A moderate increase in chain length could not explain a decrease in the overall crystallization rate. This result is probably due to the presence of branches interrupting the crystallizable sequences in reactive extruded r-PET (REX-r-PET). A rheological investigation performed by SAOS/LAOS/elongational studies detected important structural modifications in REX-r-PET with respect to linear r-PET or a reference virgin PET. REX-r-PET is characterized by a slow relaxation process with enlarged elastic behaviors that are characteristic of a long-chain branched material. The mechanical properties of REX-r-PET increased because of the addition of the chain extender without a significant loss of elongation at the break. The reactive extrusion process is a suitable way to recycle opaque PET into a material with enhanced rheological properties (thanks to the production of a chain extension and long-chain branches) with mechanical properties that are comparable to those of a typical virgin PET sample.


2019 ◽  
Vol 968 ◽  
pp. 96-106
Author(s):  
Oleksandr Pshinko ◽  
Olena Hromova ◽  
Dmytro Rudenko

Study of rheological properties of concrete mixtures based on modified cement systems in order to determine process parameters. Methodology. To study structural-mechanical properties of modified concrete mixtures of different consistency at their horizontal vibrating displacement an oscillatory viscometer was designed. Results. The optimization of the process of vibration displacement of concrete mixtures with the specification of parameters of vibration impacts taking into account structural-mechanical properties of the mixture is performed. It has been established that the viscosity of the modified cement system of the concrete mixture is a variable quantity, which depends on the parameters of the vibration impacts. Scientific novelty. The mechanism of interaction of the modified concrete mixture with the form and the table vibrator during its vibration compaction is determined. On the basis of this, a model of concrete laying process control is proposed, that allows to predict the ability to form a dense concrete structure. Practical significance. Disclosed physical nature of the process of vibrating displacement of modified concrete mixtures using the principles of physical-chemical mechanics of concrete allows reasonably choose the best options for vibration impacts.


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