Effects of bridged DOPO derivatives on the thermal stability and flame retardant properties of poly(lactic acid)

Lignin–silica hybrids (LSHs) were prepared by sol–gel method and characterized by Fourier transform infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). LSH and ammonium polyphosphate (APP) were added into poly(lactic acid) (PLA) as a novel intumescent flame-retardant (IFR) system to improve the flame retardancy of PLA. The flame-retardant effect of APP and LSH in PLA was studied using limiting oxygen index (LOI), vertical burning (UL-94) tests and cone calorimeter. The thermal stability of PLA/APP/LSH composites was evaluated by thermogravimetric analysis (TGA). Additionally, the morphology and components of char residues of the IFR-PLA composites were investigated by SEM and XPS. With the addition of APP/LSH to PLA system, the morphology of the char residue has obviously changed. Compared with PLA/APP and PLA/APP/lignin, a continuous and dense intumescent charring layer with more phosphor in PLA composites is formed, which exhibits better flame retardancy. All the results show that the combination of APP and LSH can improve the flame-retardant property and increase the thermal stability of PLA composites greatly.

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Improving the flame retardance and melt dripping of poly(lactic acid) with a novel polymeric flame retardant of high thermal stability

Fire and Materials ◽

10.1002/fam.2389 ◽

2016 ◽

Vol 41 (4) ◽

pp. 362-374 ◽

Cited By ~ 5

Author(s):

Xiaowei Shi ◽

Fenghui Liao ◽

Yaqing Ju ◽

Xiu Dai ◽

Yu Cao ◽

...

Keyword(s):

Thermal Stability ◽

Lactic Acid ◽

Flame Retardant ◽

High Thermal Stability ◽

Poly Lactic Acid ◽

Flame Retardance

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Preparation of microcellular poly(lactic acid) composites foams with improved flame retardancy

Journal of Cellular Plastics ◽

10.1177/0021955x16633644 ◽

2016 ◽

Vol 53 (1) ◽

pp. 45-63 ◽

Cited By ~ 9

Author(s):

Kun Wang ◽

Jingjing Wang ◽

Dan Zhao ◽

Wentao Zhai

Keyword(s):

Lactic Acid ◽

Flame Retardant ◽

Oxygen Index ◽

Poly Lactic Acid ◽

Limited Oxygen Index ◽

Cell Structures ◽

Phosphorus Containing ◽

Flame Retardant Properties ◽

Index Value ◽

Limited Oxygen

In this study, flame-retardant poly(lactic acid) foams with satisfactory cell structures were prepared by microcellular foaming technology using phosphorus-containing flame retardant and graphene as the charring agent. The introduction of 5–30 wt% flame retardant increased the limited oxygen index value of poly(lactic acid) from 19.0 to 26.5–37.8% and simultaneously increased the foam expansion of poly(lactic acid) foams from 4.4 to 5.8–17.5. In addition, all the prepared poly(lactic acid)/flame-retardant composites passed the UL-94 V-0 rating. The addition of 0.5 wt% graphene increased the limited oxygen index value of poly(lactic acid)/flame-retardant composite with flame-retardant content of 15 wt% from 27.9 to 29.2%, and more graphene additions improved the antidripping behavior of poly(lactic acid) composites. The possible mechanisms of the effects of the resultant cellular structure on the flame-retardant properties of poly(lactic acid) composites were also discussed.

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An effective flame retardant containing hypophosphorous acid for poly (lactic acid): Fire performance, thermal stability and mechanical properties

Polymer Testing ◽

10.1016/j.polymertesting.2019.105940 ◽

2019 ◽

Vol 78 ◽

pp. 105940 ◽

Cited By ~ 5

Author(s):

Xingguo Wang ◽

Jun Sun ◽

Xiaodong Liu ◽

Shengling Jiang ◽

Julin Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Lactic Acid ◽

Flame Retardant ◽

Poly Lactic Acid ◽

Fire Performance ◽

Hypophosphorous Acid

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Preparation of γ-Divinyl-3-Aminopropyltriethoxysilane Modified Lignin and Its Application in Flame Retardant Poly(lactic acid)

Materials ◽

10.3390/ma11091505 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1505 ◽

Cited By ~ 6

Author(s):

Yan Song ◽

Xu Zong ◽

Nan Wang ◽

Ning Yan ◽

Xueying Shan ◽

...

Keyword(s):

Thermal Stability ◽

Lactic Acid ◽

Heat Release ◽

Flame Retardant ◽

Heat Release Rate ◽

Flame Retardancy ◽

Release Rate ◽

Poly Lactic Acid ◽

Modified Lignin ◽

Thermal Stability Of

Lignin can be a candidate as a charring agent applied in halogen-free flame retardant polymers, and incorporation of silicon and nitrogen elements in lignin can benefit to enhancing its thermal stability and charring ability. In the present work, wheat straw alkali lignin (Lig) was modified to incorporate silicon and nitrogen elements by γ-divinyl-3-aminopropyltriethoxysilane, and the modified lignin (CLig) was combined with ammonium polyphosphate (APP) as intumescent flame retardant to be applied in poly(Lactic acid) (PLA). The flame retardancy, combustion behavior and thermal stability of PLA composites were studied by the limited oxygen index (LOI), vertical burning testing (UL-94), cone calorimetry testing (CCT) and thermogravimetric analysis (TGA), respectively. The results showed a significant synergistic effect between CLig and APP in flame retarded PLA (PLA/APP/CLig) occured, and the PLA/APP/CLig had better flame retardancy. CCT data analysis revealed that CLig and APP largely reduced the peak heat release rate (PHRR) and total heat release rate (THR) of PLA, indicating their effectiveness in decreasing the combustion of PLA. TGA results exhibited that APP and CLig improved the thermal stability of PLA at high temperature. The analysis of morphology and structure of residual char indicated that a continuous, compact and intumescent char layer on the material surface formed during firing, and had higher graphitization degree. Mechanical properties data showed that PLA/APP/CLig had higher tensile strength as well as elongation at break.

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