原位成纤复合泡沫材料的研究进展

孙俊威; 蒋晶; 赵娜; 王小峰; 段同生; 李倩

doi:10.13801/j.cnki.fhclxb.20220704.001

原位成纤复合泡沫材料的研究进展

doi: 10.13801/j.cnki.fhclxb.20220704.001

孙俊威¹,
蒋晶^2, ,,
赵娜¹,
王小峰¹,
段同生³,
李倩¹

1.
郑州大学　力学与安全工程学院，微纳成型技术国家级国际联合研究中心，郑州 450001
2.
郑州大学　机械与动力工程学院，郑州 450001
3.
河南省中原塑料机械有限公司，郑州 450001

基金项目: 国家自然科学基金(U1909219)

详细信息

通讯作者:
蒋晶，博士，副教授，硕士生导师，研究方向为高分子复合材料发泡　E-mail: jiangjing@zzu.edu.cn

中图分类号: TB322
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出版历程
- 收稿日期: 2022-05-06
- 修回日期: 2022-06-04
- 录用日期: 2022-06-18
- 网络出版日期: 2022-07-05
- 刊出日期: 2023-04-15

Research progress of in-situ fibrous composite foamed material

1.
School of Mechanics and Safety Engineering, International Joint Research Laboratory for Micro-Nano Molding Technology, Zhengzhou University, Zhengzhou 450001, China
2.
School of Mechanical and Power Engineering, Zhengzhou University, Zhengzhou 450001, China
3.
Henan Province Zhongyuan Plastic Machinery CO., LTD., Zhengzhou 450001, China

Funds: National Natural Science Foundation of China (U1909219)

摘要

摘要: 原位成纤复合泡沫材料是针对原位微纤化(In-situ micro fibrillation，IMF)复合材料，基于微孔发泡工艺制备的一种泡沫材料。除了具有传统泡沫材料质轻、减震、隔热、降噪等性能外，IMF复合材料内部纤维网络结构的存在显著改善了基体的微孔发泡行为，使得原位成纤复合发泡材料成为一种兼具高强度和功能化的新型泡沫材料。首先概述了IMF复合材料的制备工艺及IMF工艺过程调控因素，重点分析了IMF网络结构对复合材料结晶和流变行为的影响，其次综述了针对不同IMF复合材料体系和微孔发泡工艺的原位成纤复合泡沫材料的制备方法和泡孔结构调控手段，阐述并列举了其力学性能强韧化机制和在隔热和油水分离领域的应用，最后展望了原位成纤复合泡沫材料未来的研究方向。
- 复合材料 /
- 原位成纤 /
- 微孔发泡 /
- 泡孔结构 /
- 网络结构
Abstract: In-situ fibrous composite foamed material is one type of foams, which is based on in-situ micro fibrillation (IMF) composites and microcellular foaming technology. In addition to the performance of traditional foamed materials such as light weight, shock absorption, insulation, noise reduction, etc., the presence of fiber network structure constructed in IMF composite can significantly improve the microcellular foaming ability of the matrix. Leading to the in-situ fibrous composite foamed material is a kind of new foam with high strength and functionality. This paper first summarized the fabrication process of IMF composites and regulatory factors. The influence of IMF network structure on the crystallization and rheological behaviors were emphatically analyzed. Then reviewed the preparation and pore structure regulation methods of in-situ fibrous composite foamed materials for various IMF composites and microcellular foaming process. The mechanism of strong mechanical properties and application in the field of heat insulation and oil-water separation were then elaborated and listed. Finally, looking forward to the future research directions of in-situ fibrous composite foamed materials.
- composites /
- in-situ fibrillation /
- microcellular foaming /
- pore structure /
- network structure

HTML全文

图 1 原位成纤(IMF)工艺过程^[13]

Figure 1. Processing scheme of in-situ microfibrillation (IMF) process^[13]

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图 2 IMF复合泡沫材料制备工艺示意图

Figure 2. Schematic illustration of IMF foam fabrication

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图 3 IMF过程对基体晶型的影响：(a) 横晶^[44]；(b) Shish-Kebab晶体^[45]；(c) γ晶^[46]

Figure 3. Influence of IMF process on crystalline form of matrix: (a) Transverse crystal^[44]; (b) Shish-Kebab crystal structure^[45]; (c) γ crystal^[46]

A, B, C—Inside the images represent the shish of iPP, the kebab of iPP induced by iPP Shish, and the Kebab of iPP induced by PET microfibers, respectively; PET—Polyethylene terephthalate; PP—Polypropylene

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图 4 (a) 聚己内酯(PCL)/聚乳酸(PLA)共混物的储能模量-频率曲线；(b) PCL/PLA IMF复合物的储能模量-频率曲线^[60]；(c) PP/PET共混物与PP/PET IMF复合物的单轴拉伸-黏度曲线；(d) PP/PET IMF复合材料的拉伸应变硬化系数^[46]

Figure 4. (a) Storage modulus-frequency curves of polycaprolactone (PCL)/polylactic acid (PLA) blends; (b) Storage modulus-frequency curves of PCL/PLA IMF compound^[60]; (c) Curves of uniaxial extensional viscosity of PP/spherical-PET and PP/fibrillated-PET blends;(d) Strain hardening factor^[46]

η_E(t, ε)—Uniaxial extensional viscosity; 3η⁺—The 3-fold linear viscoelasticity; F—Nanofibrillar; S—Spherical

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图 5 PBT/PTFE复合泡沫的SEM形貌图与泡孔参数：(a) PBT/PTFE-0(phr)；(b) PBT/PTFE-0.25(phr)；(c) PBT/PTFE-0.5(phr)；(d) 平均泡孔尺寸和密度；(e) 发泡倍率^[67]

Figure 5. SEM images and parameters of PBT/PTFE composite foams: (a) PBT/PTFE-0(phr); (b) PBT/PTFE-0.25(phr); (c) PBT/PTFE-0.5(phr); (d) Average cell size and cell density; (e) Expansion ratio^[67]

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图 6 PCL/PLA微纤化复合泡沫材料开孔示意图^[60]

Figure 6. Cell opening mechanism for PCL/PLA composites foams^[60]

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图 7 PP/PTFE原位成纤复合物泡沫的拉伸性能：(a) 应力-应变曲线；(b) 屈服强度、模量和拉伸韧性^[6]

Figure 7. Tensile properties of PP/PTFE fibrillated foams: (a) Stress-strain curves; (b) Yielding strength, modulus, and tensile toughness^[6]

RFIM—Regular foam injection molding; MOFIM—Mold-opening foam injection molding

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图 8 (a) PLA/PET IMF复合泡沫微纳多层泡孔结构^[68]；(b) 纳米多孔结构的热传导机制示意图^[87]

Figure 8. (a) Hierarchically porous foam morphology of PLA/PET IMF composites foams^[68]; (b) Schematic illustration of the conductivity mechanism in hierarchically porous foam^[87]

l—Mean free path of a gas molecule; d—Pore diameter

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表 1 3种微孔发泡成型工艺技术比较

Table 1. Comparative techniques among three different microcellular foaming processes

Comparative points	BF	MEF	MCIM
Type	Non-continuous	Continuous	Continues
Sample state	Solid	Molten	Molten
Shape of sample	Simple	Medium	Complicated
Raw material required (amount)	Small	Large	Medium to large
Pore structure	Uniform and easy to obtain pores with small size and high density	Uniform and easy to obtain pores with high expansion ratio	Non-uniform and “skin-core” porous structure
Fiber size change	No effect	Increase	Increase
Dispersion of fiber	No effect	Forming fibril clusters	Forming fibril clusters
Gas dissolution rate	Low	High	High
Cause of thermodynamic instability	$\displaystyle\left(+\dfrac{\partial T}{\partial {t} }\right)\;{\rm{or} }\;\left(-\dfrac{\partial P}{\partial {t} }\right)$	Only $\displaystyle\left(-\dfrac{\partial P}{\partial t}\right)$	Only $\displaystyle\left(-\dfrac{\partial P}{\partial {t} }\right)$
Cycle time	Long time	Moderate	Less
Use	Lab scale	Commercial	Commercial
Cost	Cheap	More expensive	The most expensive
Notes: BF—Batch foaming; MEF—Microcellular extrusion foaming; MCIM—Microcellular injection molding; T—Temperature; P—Pressure; t—Time.

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表 2 IMF复合材料微孔发泡研究进展

Table 2. Research progress on microcellular IMF composite foaming

Types	Material	Fiber content/ diameter/nm	Foaming process	Cell size/μm	Cell density/ (cells·cm⁻³)	Findings	Ref.
Polyolefins	PP/PET	5wt%/210	MEF	—	10⁸-10⁹	The tensile strength of IMF composite foam was nearly double that of pure PP, and the expansion ratio was enhanced by 3 times	[65]
	PP/PBT	4wt%/100-300	BF	100	10⁶-10⁷	The presence of PBT fibers enhanced expansion ratio and cell density, as well as greatly improved thermal insulation property	[55]
	PE/PP	5wt%/100-300	BF	27.6	9.8×10⁸	Compared with pure PE foam, the cell density of IMF foam increased by four orders of magnitude	[61]
PTFE reinforced composites	PET/PTFE	1wt%/200-500	BF	2-22	10¹¹	The PET foams with 1wt% PTFE possessed the smallest cell diameter and the highest cell density	[69]
	PP/PTFE	4wt%/<500	MEF	50-500	10⁷-10⁸	Superhydrophobic and lipophilic open-cell foams were prepared with an open cell ratio of up to 97.7%	[21]
	PP/PTFE	5wt%/143	MCIM	35	10⁸	Compared with pure PP foam, the cell density of IMF composite foam enhanced by four orders of magnitude, the open cell rate reached 98.3%	[70]
Elastomer resins	TPEE/PTFE	5wt%/<200	MEF	10.4	8.6×10⁷	As against pure TPEE foam, the expansion ratio of IMF composite foam enhanced by nearly 10 times	[66]
Elastomer resins	TPU/PTFE	3wt%/ 290-340	BF	24	10⁸	The presence of PET fibers enhanced the expansion ratio and cell density	[71]
Bio- degradable materials	PCL/PLA	20wt%	BF	8	3.9×10⁶	Fibers induced larger open cell ratios in PCL/PLA blend foam	[60]
	PLA/PA6	3wt%/198	BF	23	1.8×10⁸	The cell density of PLA/PA6 IMF composite foam increased by two orders of magnitude compared with pure PLA foam	[22]
	PLA/PET	10wt%/114.8	MCIM	0.32	1.1×10¹³	IMF composite with PET average fiber diameter of 114.8 nm and IMF composite foam with nano-scale pores were prepared	[68]
Notes: PP—Polypropylene; PBT—Polybutylene terephthalate; PE—Polyethylene; PTFE—Poly tetrafluoroethylene; TPEE—Thermoplastic polyester; TPU—Thermoplastic polyurethane; PA6—Polyamide 6.

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