Fabrication and Properties of Thermoplastic Polyurethane/Microencapsulated Ammonium Polyphosphate/Aluminum Hydroxide Composites

doi:10.19491/j.issn.1001-9278.2021.07.006

Abstract

Abstract:

The microencapsulated ammonium polyphosphate （MAPP） with a silicone gel was prepared through a sol?gel method and then characterized with fourier transform infrared spectrometer and thermogravimetric analyzer （TG）. MAPP and aluminum hydroxide （ATH） were used as flame retardant to prepare a series of flame?retardant thermoplastic polyurethane composites （TPU/FR） by means of a melt?bending technology. TG， and microscale combustion calorimeter were used to analyze the thermal stability and combustion behaviors of the TPU/FR composites. The results indicated that with the fixed total loading of ATH and MAPP at 20 wt%， the composites achieved char yields of 29.7 wt%， 25.1 wt% and 20.9 wt% at mass ratios of ATH to MAPP of 5/15， 10/10 and 15/5 at 700 ℃， respectively， compared to the composites containing only 20 wt% ATH with a char yield of 16.7 wt%. Their heat release capacity decreased to 154.2， 164.2 and 170.1 J/（g·K） from 327.1 J/（g·K） of the composite only containing ATH. Moreover， compared to composites containing only 20 wt% of MAPP， there is a significant improvement in the compactness and graphitization degree of the carbon slag for TPU/FR4（15 wt% ATH，5 wt% MAPP）， indicating that a combination of ATH and MAPP generated a significant flame?retardant synergistic effect.

Key words: microencapsulated ammonium polyphosphate, aluminum hydroxide, thermoplastic polyurethane, composite, flame retardant

CLC Number:

TQ323.8

PENG Jianwen, LIU Xinliang, XIAO Chong, SONG Qiang, PENG Zhongchao, HUANG Ruosen, TANG Gang. Fabrication and Properties of Thermoplastic Polyurethane/Microencapsulated Ammonium Polyphosphate/Aluminum Hydroxide Composites[J]. China Plastics, 2021, 35(7): 36-42.

Figures/Tables 12

References 25

1	ZHANG J H， KONG Q H， YANG L W， et al. Few Layered Co（OH）₂ Ultrathin Nanosheet⁃based Polyurethane Nanocomposites with Reduced Fire Hazard： From Eco⁃friendly Flame Retardance to Sustainable Recycling［J］. Green Chemistry， 2016， 18（10）： 3 066⁃3 074.
2	朱雨露. 石墨烯、氮化碳基杂化物的制备及其聚氨酯阻燃性能的研究［D］. 合肥：中国科学技术大学， 2017.
3	GULER T， TAYFUN U， BAYRAMLI E， et al. Effect of Expandable Graphite on Flame Retardant， Thermaland Mechanical Properties of Thermoplastic Polyurethanecomposites Filled with Huntite & Hydromagnesite Mineral［J］. Thermochimica Acta， 2017， 647： 70⁃80.
4	DIKE A S， TAYFUN U， DOGAN M. Influence of Zinc Borate on Flame Retardant and Thermal Properties of Polyu⁃rethane Elastomer Composites Containing Huntite⁃hydromagnesite Mineral［J］. Fire and Materials， 2017， 41（7）： 890⁃897.
5	HE L X， WANG J L， WANG B B， et al. Large⁃scale Production of Simultaneously Exfoliated and Functionalized Mxenes as Promising Flame Retardant for Polyurethane［J］. Composites Part B： Engineering， 2019， 179： 107486.
6	ADRIAN C， STUART H， MOHAMED A E A， et al. Novel Brominated Flame Retardants： A Review of Their Analysis， Environmental Fate and Behaviour［J］. Environment International， 2011， 37（2）： 532⁃556.
7	刘继纯，于卓立，陈梁，等. Mg（OH）₂⁃Al（OH）₃⁃微胶囊红磷/高抗冲聚苯乙烯无卤阻燃复合材料［J］. 复合材料学报， 2013， 30（4）： 36⁃43.
	LIU J C， YU Z L， CHEN L， et al. Halogen⁃free Flame Retardant Mg（OH）₂⁃Al（OH）₃⁃MRP/HIPS Composites［J］. Acta Materiae Compositae Sinica， 2013， 30（4）： 36⁃43.
8	窦艳丽，李雪菲，张天琪，等. β⁃环糊精⁃聚磷酸铵对黄麻/聚丙烯复合材料阻燃性能的影响［J］. 复合材料学报， 2019， 36（11）： 2 568⁃2 578.
	DOU Y L， LI X F， ZHANG T Q， et al. Effect of β⁃cyclodextrin and Ammonium Polyphosphate on Flame Retardancy of Jute/Polypropylene Composites［J］. Acta Materiae Compositae Sinica， 2019， 36（11）： 2 568⁃2 578.
9	CHEN X L， JIANG Y F， LIU J B， et al. Smoke Suppression Properties of Fumed Silica on Flame⁃retardant Thermoplastic Polyurethane Based on Ammonium Polyphosphate［J］. Journal of Thermal Analysis and Calorimetry， 2015， 120（3）： 1 493⁃1 501.
10	LIU C， ZONG R W， CHEN H Y， et al. Comparative Study of Toxicity for Thermoplastic Polyurethane and Its Flame⁃retardant Composites［J］. Journal of Thermoplastic Composite Materials， 2018， 32（10）： 1 393⁃1 407.
11	HUANG S C， DENG C， WANG S X， et al. Electrosta⁃tic Action Induced Interfacial Accumulation of Layered Double Hydroxides Towards Highly Efficient Flame Retardance and Mechanical Enhancement of Thermoplastic Polyurethane/Ammonium Polyphosphate［J］. Polymer Degradation and Stability， 2019， 165： 126⁃136.
12	GAO W Y， QIAN X D， WANG S J. Preparation of Hybrid Silicon Materials Microcapsulated Ammonium Polyphosphate and Its Application in Thermoplastic Polyurethane［J］. Journal of Applied Polymer Science， 2018， 135（4）： 45742.
13	XU L F， LEI C H， XU R J， et al. Synergistic Effect on Flame Retardancy and Thermal Behavior of Polycarbonate Filled with α⁃zirconium Phosphate@Gel⁃Silica［J］. Journal of Applied Polymer Science， 2017， 134（19）：44829.
14	周陆陆，杜建新，杨荣杰. 硅⁃磷阻燃剂对热塑性聚氨酯弹性体阻燃性能的影响［J］. 高分子材料科学与工程， 2018， 34（11）： 79⁃85.
	ZHOU L L， DU J X， YANG R J. Effect of Silicon⁃phosphorus Flame Retardants on Performances of Polyurethane Elastomer［J］. Polymer Materials Science and Engineering， 2018， 34（11）： 79⁃85.
15	PANG H C， WANG X S， ZHU X K， et al. Nanoengineering of Brucite@SiO₂ for Enhanced Mechanical Properties and Flame Retardant Behaviors［J］. Polymer Degradation and Stability， 2015， 120： 410⁃418.
16	CHEN Y J， LI L S， XU L F， et al. Phosphorus⁃containing Silica Gel⁃coated Ammonium Polyphosphate： Preparation， Characterization， and Its Effect on The Flame Retardancy of Rigid Polyurethane Foam［J］. Journal of Applied Polymer Science， 2018， 135（22）：46334.
17	YU S W， XIAO S J， ZHAO Z W， et al. Microencapsulated Ammonium Polyphosphate by Polyurethane with Segment of Dipentaerythritol and Its Application in Flame Retardant Polypropylene［J］. Chinese Journal of Chemical Engineering， 2019， 27（7）： 1 735⁃1 743.
18	YANG K， XU M J， LI B. Synthesis of N⁃ethyl Triazine⁃piperazine Copolymer and Flame Retardancy and Water Resistance of Intumescent Flame Retardant Polypropylene［J］. Polymer Degradation and Stability， 2013， 98（7）： 1 397⁃1 406.
19	KANG X L， LIU Y， CHEN N X， et al. Influence of Modified Ammonium Polyphosphate on the Fire Behavior and Mechanical Properties of Polyformaldehyde［J］. Journal of Applied Polymer Science， 2020： 50156.
20	陈博，房轶群，司月月，等. 胶合板表面层层自组装聚磷酸铵⁃纳米氮化硼/壳聚糖薄膜及其阻燃性能［J］. 复合材料学报， 2021， 38（4）： 1 252⁃1 261.
	CHEN B， FANG Y Q， SI Y Y， et al. Flame Retardancy of Ammonium Polyphosphate⁃nano Boron Nitride/ Chitosan Coatings on Plywood Surface Via Layer⁃by⁃layer Selfassembly Method［J］. Acta Materiae Compositae Sinica， 2021， 38（4）： 1 252⁃1 261.
21	WANG S W， SHI M N， YANG W M， et al. Experimental Investigation of Flame Retardancy and Mechanical Properties of APP/EG/TPU Multilayer Composites Prepared by Microlayer Coextrusion Technology［J］. Journal of Applied Polymer Science， 2020： 50219.
22	TANG G， WANG X， XING W Y， et al. Thermal Degradation and Flame Retardance of Biobased Polylactide Composites Based on Aluminum Hypophosphite［J］. Industrial & Engineering Chemistry Research， 2012， 51（37）： 12 009⁃12 016.
23	WANG Y C， ZHANG L， YANG Y Y， et al. Synergistic Flame Retardant Effects and Mechanisms of Aluminum Diethylphosphinate （AlPi） in Combination with Aluminum Trihydrate （ATH） in UPR［J］. Journal of Thermal Analysis and Calorimetry， 2016， 125（2）： 839⁃848.
24	王靖宇，郝建薇.无卤阻燃硬质聚氨酯泡沫塑料的研究进展［J］. 中国塑料， 2020， 34（5）： 107⁃114.
	WANG J Y， HAO J W. Research Progress in Halogen⁃free Flame⁃retardant RPUF［J］. China Plastics， 2020， 34（5）： 107⁃114.
25	TANG G， LIU X L， ZHOU L， et al. Steel Slag Waste Combined with Melamine Pyrophosphate as A Flame Retardant for Rigid Polyurethane Foams［J］. Advanced Powder Technology， 2020， 31（1）： 279⁃286.

样品名称	T _5%/oC	T_max1 /oC	T_max2 /oC	700 oC残炭量/%
APP	331	361	606	10.5
MAPP	295	300	569	32.3

样品名称	T _5%/oC	T_max1 /oC	T_max2 /oC	700 oC残炭量/%
APP	331	361	606	10.5
MAPP	295	300	569	32.3

样品名称	T_{5 %}/oC	T_{50 %}/oC	T_max1/oC	T_max2/oC	T_max3/oC	700 oC 残炭量/%
TPU	314	406	334	425	-	3.3
TPU/FR1	299	408	332	419	-	16.7
TPU/FR2	300	370	310	338	470	30.3
TPU/FR3	298	381	310	339	468	29.7
TPU/FR4	296	391	310	360	-	25.1
TPU/FR5	300	406	316	420	-	20.9

样品名称	T_{5 %}/oC	T_{50 %}/oC	T_max1/oC	T_max2/oC	T_max3/oC	700 oC 残炭量/%
TPU	314	406	334	425	-	3.3
TPU/FR1	299	408	332	419	-	16.7
TPU/FR2	300	370	310	338	470	30.3
TPU/FR3	298	381	310	339	468	29.7
TPU/FR4	296	391	310	360	-	25.1
TPU/FR5	300	406	316	420	-	20.9

样品名称	HRC/ J·（g·K）^-1	热释放速率峰值/W·g^-1	热释放速率峰值温度/oC	总热释放量/kJ·g^-1
TPU	510.2	127.5/509.7	374/443	30.8
TPU/FR1	327.1	124.1/322.8	365/446.6	24.0
TPU/FR2	253.8	234.5/35.6	351.5/477.1	16.9
TPU/FR3	154.2	153.7/118.0	326.6/381.7	18.1
TPU/FR4	164.2	160.9/160.6	331.3/409.1	20.2
TPU/FR5	170.1	169.5/170.2	327.8/418.7	19.6