Foam Density Research Articles

A study of the cell morphology and mechanical properties of bumper material PP-T-EPDM composite foam

In this study, cellular polypropylene based composite foams were prepared using an universal injection moulding machine. The chemical foaming agent was added to neat polypropylene (PP) polymer, talc filled polypropylene (PP-T) composite and talc filled polypropylene/ethylene-propylene-diene blend (PP-T-EPDM) composite materials at the ratio of 1% and 2% by weight. The influence of foaming agent content on the mechanical and cellular properties of both neat PP polymer and PP composites was investigated. The results showed that the tensile strength, tensile modulus, impact strength, hardness, cell diameter, foam density and viscosity values and skin layer thickness decreased while volume expansion ratio increased with the increment in chemical blowing agent content.

Carbon Foams by Solid State Foaming of Short Vermicelli Bonded by Phenol-Formaldehyde for Thermal Insulation and Electromagnetic Interference Shielding

A simple method of production of carbon foams by randomly assembling short vermicelli rods and bonding them using phenol-formaldehyde (PF) followed by foaming in the solid state during carbonization has been reported. The brittle vermicelli becomes ductile in the range of 200–250 °C during carbonization, which facilitates the nucleation and growth of bubbles in the solid state due to the water vapor generated by the -OH condensation of starch. The dense PF coating on the vermicelli surface facilitates the enlargement of cells by restricting the escape of water vapor during the solid state foaming. The dense carbon produced from the PF binds the carbonized vermicelli rods, affording structural integrity and mechanical strength. The foam body consists of open intervermicelli void space and closed cellular pores in the carbonized vermicelli rods. A broad cell size range of 4–142 μm with an average value of 29.2 μm is observed. The density, compressive strength, and thermal conductivity of the carbon foam are modulated in the ranges of 0.30–0.34 g cm–3, 0.63–1.6 MPa, and 0.162–0.222 W m–1 K–1, respectively, by changing the PF solution concentration in the range of 50–90 vol %. The carbon foams exhibit absorption-dominated electromagnetic interference shielding with total shielding effectiveness and specific shielding effectiveness in the ranges of 47.5–65.6 dB and 155.2–192.9 dB cm3 g–1, respectively, for the X band (8.2–12.4 GHz).

Construction of a Highly Oriented Poly(lactic acid)-Based Block Polymer Foam and Its Self-Reinforcing Mechanism

Developing poly(lactic acid) (PLA)-based biodegradable polymer foams with high performance is crucial for sustainable energy conservation and the ecological environment. In this work, by applying poly(lactide-co-caprolactone) (PLCL) as a compatibilizer, the block polymer of poly(l-lactic) acid (PLLA)-b-polycaprolactone (PCL) with a long-chain branched structure was prepared by reactive processing. By utilizing the difference between the glass-transition temperature (Tg) and melting temperature (Tm) of PLA and PCL, PLLA-b-PCL-PLCL foams with a PCL chain as the foaming phase and an oriented PLLA chain as the enhancing phase were prepared by establishing a solid-phase hot drawing@supercritical CO2 foaming method. The incorporation of PLCL links significantly improved the interfacial compatibility between PLLA and PCL phases and chain entanglements, exhibiting strain-hardening behavior and leading to an improvement in the stretchability of the block polymer. In the hot drawing process in the range of Tg(PLA)–Tm(PLA), both PLLA and PCL phases were elongated along the drawing direction, and with an increasing draw ratio, the orientation factor and the crystallinity of the two phases increased evidently, accompanied by the formation of a shish–kebab crystalline structure. In the subsequent foaming process in the range of Tg(PCL)–Tm(PCL), the molecular chains of the PLLA phase were frozen and the retention of the orientation factor reached over 90%, while under CO2, crystallinity and crystallite size increased and a more perfect crystalline structure formed for the PCL phase. With an increasing draw ratio, the saturated dissolved amount of CO2 increased and the cell density and cell size of foam reached 5.13 × 109 cells/cm3 and 4.06 μm, respectively. The fibrillar structures of the PLLA phase appeared on the cell wall, while the tensile strength and modulus of foam reached as high as 65.9 MPa and 1.01 GPa, respectively. As a result, a super-strong PLA-based microcellular foam with dense micropores and highly oriented microfibrillar structures was constructed.

Al-Foam Compression Tests in Parallel and Serial Concepts

Taking into consideration the additional weight of a vehicle, today’s requirements can only be met using new materials and designs. The application of metal foam is one of the most promising methods of enhancing the impact energy absorption ability of the crumple zone. The energy-absorbing capacity of thin-walled structures filled with metal foams during compression can be notably improved, which results in lower loading on the passengers. The main goal of our research is to develop a new design that is suited to absorb more impact energy while taking into consideration weight optimization. The authors wanted to unveil the effect of the inhomogeneous filler material in these thin-walled structures. Therefore, the present study investigates the compression test of two metal foams of different densities, in different ways. In the first section, the foams were compressed independently from each other by a recording of a stress–strain diagram. After the single compression, the foams were loaded together, first in parallel, and subsequently in a serial scheme. The study aimed to reveal the effect of the parallel and serial compression scheme focusing on the sum of impact energy absorption.

Preparation of metakaolin-fly ash cenosphere based geopolymer matrices for passive fire protection

In this paper, fly ash cenosphere (FAC) with spherical and hollow structure has been adopted as a pore-forming agent to prepare low density and high strength geopolymer foams. Serial analyses of physical properties, mineral characterization, and thermostability have been employed to investigate the feasibility of metakaolin (MK)-FAC based geopolymer for passive fire protection. FAC addition not only significantly decreases the dry bulk density and thermal conductivity of geopolymer blocks, but also helps to achieve acceptable compressive strength. Meanwhile, FAC addition into geopolymer matrices has brought obviously negative effects on heat transfer and led to the reaction enthalpy rise under high temperature. Owing to the conversion of the amorphous geopolymer gel at the surface to ceramics and excellent thermal insulation performance, the reverse-side temperatures of the geopolymer specimens with FAC addition from 30 to 90 wt% always maintain at about 260 °C until the end of the fire resistance tests. Although weak reactions between alkali activator and FAC have happened and enhanced the bonding between FAC and geopolymer gels, the improvement in physical properties of the MK-FAC based geopolymers would mainly be attributed to the physical characteristics of the FAC. This study could open opportunities to employ MK-FAC geopolymers as alternatives in the application of thermal insulation and fire protection.

Study on fire extinguishing performance of different foam extinguishing agents in diesel pool fire

The physical properties and fire extinguishing performance in diesel fire of aqueous film-forming foam (AFFF) and protein foam (PF) were studied, and the fire extinguishing mechanism of different foams were also analyzed. The results show that 6%AFFF and 6%PF have better performance than that of 3%AFFF and 3%PF, respectively, and AFFF possess higher expansion ratio, 25% drainage time and surface tension than PF at the same concentration. The fire extinguishing test show that the extinguishing performance of foam enhanced with the increase of gas-liquid ratio firstly, and decreased subsequently. The best fire extinguishing performance were achieved when gas-liquid ratio of 6%AFFF and 6%PF were 17 and 20, and the extinguishing agent dosage were 229 ml and 260 ml, respectively. Compared with PF, the fire extinguishing time and agent dosage of AFFF are reduced by 10% and 6.15% respectively at gas-liquid ratio of 20. Besides, AFFF can form more dense, stable and high-multiple foam cover layer, endow it with better fire extinguishing performance than PF. However, PF can reduce the temperature around the oil pool more quickly, showing better cooling effect than AFFF.

Flexible pressure/temperature sensing system based on Te-PEDOT:PSS composite thermoelectric material

<p indent="0mm">With the rapid development of artificial intelligence, the demand for new flexible tactile sensors for human-machine interaction technology is increasing sharply. As an essential medium for intelligent bionic systems to obtain external information, such as intelligent manipulators and bionic prosthetic hands, flexible tactile sensors are significant for realizing bionic tactile perception and improving system intelligence. Recently, fabricating multimodal tactile sensors through theoptimal design of functional material and structure has become a key challenge in the field of flexible electronics. Herein, a thermoelectric sensing material composited of Te-poly (3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (Te-PEDOT:PSS) was prepared via a hydrothermal method, which was compounded within a three-dimensional porous dense amine foam framework and subsequently coated by a thin polyvinyl alcohol layer for encapsulation. The controllable preparation of sensitive composite materials with high interfacial stability was realized. Thus, the assembled flexible tactile sensor with a thermoelectric effect and capacitance performance can achieve the perception ability of pressure/temperature in contact/noncontact mode, respectively. Further, an intelligent manipulator sensory feedback system is constructed, and its performance in tactile perception is explored.

Effect of nano‐sized zinc citrate on the supercritical carbon dioxide‐assisted extrusion foaming behavior of poly(lactic acid)

AbstractPoly(lactic acid) (PLA) foams containing various amounts of an epoxy as a chain extender (CE) and nano‐sized zinc citrate as a nucleating agent are prepared by continuous extrusion using supercritical CO2 (sc‐CO2) as a physical foaming agent. Processing parameters such as the CE content, sc‐CO2 flow rate, and foaming temperature are optimized with regard to the apparent density and expansion ratio of the PLA foams. The nano‐sized zinc citrate exhibits a high nucleation activity for the crystallization of the PLA. The addition of 0.5 wt% nano‐sized zinc citrate significantly increases the compressive strength and modulus of the PLA foams from 0.124 MPa and 3.1 MPa to 0.35 MPa and 19 MPa, respectively. The PLA/0.5 wt% nano‐sized zinc citrate foam shows a microcellular structure with an average cell diameter of 17.1 μm.

Hierarchical Macroporous PolyDCPD Composites from Surface-Modified Calcite-Stabilized High Internal Phase Emulsions

High Internal Phase Emulsions (HIPEs) of dicyclopentadiene (DCPD) were prepared using mixtures of surface-modified calcite (mCalcite) and a non-ionic surfactant. Twelve different emulsion formulations were created using an experimental design methodology. Three distinctive levels of the internal phase ratio, the amount of mCalcite loading, and the surfactant were used to prepare the HIPEs. Accordingly, macroporous polyDCPD composites were synthesized by performing ring-opening metathesis polymerization (ROMP) on the HIPEs. The variations in the morphological and physical properties of the composites were investigated in terms of experimental parameters. In the end, five different model equations were derived with a confidence level of 95%. The main and binary interaction effects of the experimental parameters on the responses, such as the average cavity size, interconnecting pore size, specific surface area, foam density, and compression modulus, were demonstrated. The synergistic interaction between the amount of surfactant, the amount of mCalcite loading, and the internal phase ratio appeared to have a dominant role in the average cavity diameter. The solo effect of the internal phase ratio on the interconnecting pore size, foam density, and compression modulus was confirmed. In addition, it was demonstrated that the specific surface area of the composites was mainly changed depending on the amount of mCalcite loading.

Investigation of rheological properties of semi-finished products for oriental confectionery based on gluten-free raw materials

This article is devoted to the study of rheological properties of finished dough semi-finished products for oriental confectionery based on gluten-free raw materials. Rice and corn flour were used as the main raw materials. Foam density was determined as the ratio of a certain foam mass to the volume of the vessel measured with distilled water, foaming ability – as the ratio of the height of the foam column to the height of the column of the solution of prescription components, foam stability – as the ratio of the height of the foam after 3 hours to the original. Organoleptic quality indicators were determined in accordance with GOST R 50228-92. The tasting quality assessment was carried out by a 10-point school. The structural and mechanical properties of the chak-chak samples were studied on the texture analyzer "Structurometer ST-3" by determining the loading force on the indenter when it is inserted into the sample body at a movement speed (insertion) of 1.0 mm/s. As a result of the conducted research, it was concluded that the optimal ratio of rice and corn flour is 1:1, in this ratio, semi-finished products are characterized by high organoleptic and structural-mechanical quality indicators that are not inferior to the control sample of semi-finished products. The use of rice and corn flour in the chakchak technology makes it possible to expand the range of gluten-free oriental flour confectionery products suitable for consumption by people suffering from such a disease as celiac disease.

Eksperimentalno istraživanje toplotno-hidrauličkih performansi kanala sa pregradama od gradijentne metalne pene

Metal foam is a novel material recently utilized in baffles as an alternative to solid baffles for reducing flow resistance. However, the metal foam baffles are accompanied by low heat transfer efficiency. To overcome this issue, a new design of copper foam baffles has been suggested in this research, called baffles having a gradient pore density of the copper foam. The pore density either increases or decreases towards the wall. So, the experimental tests were carried out in a square channel and heated uniformly at the bottom wall of the test section. Its walls are mounted copper foam baffles at a fixed porosity of 95%. Baffles were alternately fixed upon the walls' bottom and top in staggered mode. The results were determined for various kinds of copper foam (10 and 20) pores per inch (PPI), and the gradient pore density was either with the order decreasing (DPPI) 10/20 PPI or increasing (IPPI) 20/10 PPI with a window cut ratio of 25% and a constant heat flux of 4.4 kW/m2 . The Reynolds number was changed from 3.8x104 to 5.4x104 . The data for conventional copper solid baffles were used to compare the influence of foam metal type. The obtained results revealed an enhancement in thermohydraulic performance for baffles with a gradient pore density of the order decreasing DPPI (10/20 PPI) higher than all the models of copper foam baffles.

Физико-химические и термические превращения газонаполненной полимерной теплоизоляции естественного старения

Introduction. In the process of operation, various materials are subjected to prolonged exposure to environmental factors, which can lead to irreversible physical and chemical changes that affect not only their service life, but also fire safety. In this regard, the study of the influence of natural ageing on the features of the combustion process, fire hazard characteristics of thermal insulation materials is relevant. Aims and objectives. The aim of the work is to evaluate the physicochemical and thermal transformations of polymer gas-filled thermal insulation (expanded polystyrene foam) of long-term natural ageing. Methods. A set of physicochemical methods, namely X-ray phase analysis, infrared spectroscopy and thermal analysis methods (TG, DTG, DSC) were used to study the physicochemical nature and thermal stability of naturally aged polystyrene foam. Results and discussion. In the work the technical condition of polymer thermal insulation was assessed on the objects: cinema "Udarnik" (Russia, Moscow), 1927-1930 year of construction and a residential building (Tajikistan, Vahdat), 2014 year of construction. The method of X-ray phase analysis for polystyrene foam of natural ageing revealed a decrease in crystallinity. The change in the phase state of polymer thermal insulation indicates the thermal fluctuation nature of the processes associated with its natural aging and leading to a change in the ordering of the arrangement of individual macromolecular sites of aromatic hydrocarbon. At the same time, under the conditions of natural ageing there is a decrease in the apparent density of polystyrene foam by 20-41 %. By method of infrared spectroscopy the greatest changes are established in areas of characteristic absorption bands 3057...2846 cm-1, and also 1500...1450 cm-1, that testifies to destabilisation of hydrocarbon chains of macromolecules of polystyrene foam of natural ageing. The character of thermo-destructive transformations is established for the investigated samples, the tendency of expansion of the main section (335...470 °С) in comparison with the samples without natural ageing (360...450 °С) is revealed. The identified features of physicochemical and thermal transformations of naturally aged polystyrene foam can lead to changes in the intensity of the combustion process and heat release. Conclusion. According to the results of the study it is established that in the process of natural ageing in gas-filled polymers irreversible physical and chemical changes occur under the influence of environmental factors. Deterioration of the technical condition of polymer thermal insulation during its operation can lead to changes in the characteristics of fire hazard, features of its combustion and heat release when exposed to fire. Keywords: thermal insulation; polymers; polystyrene foam; fire hazard; service life; natural ageing.

INFLUENCE OF RAW MATERIAL PROPERTIES ON WASTE-BASED GLASS FOAM

Glass foam tablets were prepared by using mixed glass bottles (green, brown, and white), eggshell waste as a foaming agent, Na-bentonite as binder material, and red mud as an additive, respectively. The influence of the amount of red mud and fly ash on the properties (foaming temperature, mechanical strength, specimen density and porosity, thermal conductivity) of the tablets was studied. The foamed tablets contained 2.5 wt % binder material, 0.1 wt % foaming agent, 5 wt % fly ash, and red mud as additives in different ratios (0 – 40 wt %). After homogenization, the ground raw materials were pressed into tablets at 30 MPa using a hydraulic piston press. The products were heat treated at different temperatures with different heating rates. The final product’s properties were measured (specimen density, thermal conductivity, and mechanical strength through falling and abrasion resistance tests). The most convenient results were shown at 5 wt % red mud in this case, the specimen density and thermal conductivity were the lowest, the values were 0.3 g/cm3 and 0.036 W/mK. If 5 wt % of fly ash was added to the mixture the density value stayed the same, the thermal conductivity increased to 0.048 W/mK, but the mechanical strength of the tablets rapidly increased.

Frontally polymerized foams: thermodynamic and kinetical aspects of front hindrance by particles.

Frontal polymerization (FP) is a solvent-free, energy-efficient process where a self-propagating polymerization reaction with a characteristic sharp temperature gradient at the front head propagates through the resin to provide the curing conditions. It relies on the enthalpic balance, which spreads the reaction to unreacted resin in the neighborhood. Therefore, the FP is sensitive to the presence of non-reactive volumes, such as boundaries, fillers, or other additives, that retain heat from the front but produce no enthalpy in return. On the other hand, the front's high temperature could be used to initiate other processes, such as foaming, incorporating them into a simple single-step fabrication procedure. This study used silica particles of two different sizes (14 nm and 200-300 nm) in an epoxy-based FP foam as a representative filler to probe the constraints imposed by non-reactive additives. The presence of particles visibly hindered the front propagation, increased the foam density and even corrupted the frontal regime in some cases. We show that preheating or chemical composition changes are viable approaches to address the fillers' adverse effects. Furthermore, we present evidence that the reduced reaction enthalpy caused by silica nanoparticles, was balanced by the lower heat capacity of our model system. At the same time, the front hindrance was attributed to changes in reaction kinetics and the heat distribution around the front. These results set up essential narratives for the design and practical applications of frontally polymerized foams with non-reactive fillers.

Reinforcing a Thermoplastic Starch/Poly(butylene adipate-co-terephthalate) Composite Foam with Polyethylene Glycol under Supercritical Carbon Dioxide

Biodegradable foams are a potential substitute for most fossil-fuel-derived polymer foams currently used in the cushion furniture-making industry. Thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate) (PBAT) are biodegradable polymers, although their poor compatibility does not support the foam-forming process. In this study, we investigated the effect of polyethylene glycol (PEG) with or without silane A (SA) on the foam density, cell structure and tensile properties of TPS/PBAT blends. The challenges in foam forming were explored through various temperature and pressure values under supercritical carbon dioxide (CO2) conditions. The obtained experimental results indicate that PEG and SA act as a plasticizer and compatibilizer, respectively. The 50% (TPS with SA + PEG)/50% PBAT blends generally produce foams that have a lower foam density and better cell structure than those of 50% (TPS with PEG)/50% PBAT blends. The tensile property of each 50% (TPS with SA + PEG)/50% PBAT foam is generally better than that of each 50% (TPS with PEG)/50% PBAT foam.

Tailorable thermoplastic insulation foam composites enabled by porous-shell hollow glass spheres and expandable thermoplastic microspheres

We report a simple and commercially viable strategy to produce thermoplastic composite foams using synergistic foaming approaches – incorporating porous-shell hollow-interior glass spheres (PHGS) as a filler and utilizing expandable thermoplastic microspheres (EMS) as a physical blowing agent – for thermal insulation applications. The EMS in these composites ensure formation of highly porous, low-density foam while the PHGSs provide low thermal conductivity and lightweight mechanical reinforcement. Through systematic optimization of the PHGS and EMS loadings, a lightweight, and robust insulation with thermal resistivity greater than 27.7 m·K/W (R/in. > 4) is achieved. Notably, the fabricated foams also demonstrated comparable compressive strength than some commercial thermoplastic insulating materials. Through optimization of PHGS and EMS concentrations, results indicated similar thermal performance characteristics at varying foam densities, while higher loadings of both components lead to reduced insulation performance and weak mechanical stability of the foams. The results obtained, when coupled with the potential scalability and tailor ability of the overall process towards targeted insulation performance, not only endows competitiveness with current commercial thermoplastic insulating materials but also offers great promise for the development of unique thermoplastic composite foams for a variety of insulation systems.

Production and characterisation of self-blowing lignin-based foams

Self-blowing lignin-furanic foams were produced using formulations comprising Kraft lignin and furfuryl alcohol as the major components. Diethyl ether, Tween 85 and sulphuric acid were used as blowing agent, surfactant and catalyst. The influence of the components and the ratio of furfuryl alcohol to lignin was investigated with regard to the foam density, mechanical properties, water absorption, thermal properties, and fire behaviour. Depending on the formulation, the density of lignin-furanic foams ranged between 60 and 320 kg m−3. Increasing the furfuryl alcohol content increased the density of the foams. Low-density foams were obtained with a higher proportion of diethyl ether. The compression strength and modulus of elasticity (MoE) of lignin-furanic foams also increased with foam density. All lignin-furanic foams showed good thermal stability and residual masses by thermogravimetric analysis. Cone calorimetric analysis showed that lignin-furanic foams have poor flammability and self-extinguish within few seconds.

Production of porous geopolymers using ash and slag waste of power plants in the Russian Arctic

Coal combustion at thermal power plants generates much ash and slag waste which amass at waste sites and have a dramatic adverse effect on the environment. In the meanwhile, ash and slag is a valuable source for the production of silicate materials for road making and civil construction. The most promising technology for the synthesis of silicate materials is selected from the viewpoint of energy and resource efficiency&mdash;the low-temperature alkaline activation and production of porous geopolymers. A range of mix formulations is developed on the basis of ash and slag from Severodvinsk PP-1, with addition of an alkaline activator (mixture of sodium hydroxide solution and liquid glass), various sponging agents and a foam stabilizer. The increase in the amount of an alkaline activator noticeably decreases the foam stability. The aluminum powder is a less active sponging agent as compared with the hydrogen peroxide solution. The introduction of a foam stabilizer essentially increases the number of pores and decreases the foam density. The synthesis of geopolymeric materials using ash and slag from Apatity PP produced a material with the density of 456 kg/m3 and with the pores 300&ndash;600 &mu;m in size upon average. Addition of a surfactant greatly decreases the average size of pores at insignificant reduction in the density of the test samples. On the evidence of the research, the optimal composition of the activation mixture is selected for manufacturing porous geopolymeric materials with a density less than 500 kg/m3, including an alkaline activator, hydrogen peroxide as a sponging agent and a surfactant as a foam stabilizer. The study was supported by the Russian Science Foundation in the framework&nbsp;of Agreement No. 21-19-00203 Effective Heat-Curable Eco-Geopolymers&nbsp;for Road Construction in the Russian Arctic Using Combustion Waste of&nbsp;Solid Fuels at Local Power Pants under guidance by E. A. Yatsenko.

Effects of Wood Flour and Curing Temperature on Some Properties of the Polyurethane Foam Core in a Wood-Based Sandwich Panel

The objectives of this study were to examine the chemical, physical, and mechanical properties of polyurethane (PU) foam prepared with various wood flour contents and curing temperatures for use as a core layer in wood-based sandwich panels. The five alternative wood flour contents tested were 2, 4, 6, 8, 10, and 12%, and the alternative curing temperatures 100, 120, 140, and 160°C were studied with 10% wood flour content. The results showed that the cell size and density of the PU foam increased at wood contents above 6%, which reduced the compressive strength of the samples. It was also found for PU with 10% wood content that curing at 100 to 160°C caused a decrease in foam density by 50%, compared with PU foam cured under the standard conditions (i.e., at room temperature). SEM and cell size measurements show the anisotropy of PU foam and the increase of foam cell diameter when increasing the curing temperature from standard condition to 140°C. Consequently, the compressive strength and its specific value declined abruptly at elevated curing temperatures, starting from 100°C. These results suggest that elevated curing temperatures cause degradation of the properties of wood-filled PU foam, due to effects on foam cell structure.

Development of ultralight, tough and hydrophobic polymethylmethacrylate/polyvinylidene fluoride shape memory foams for heat insulation applications

Thermal insulation is vital for achieving efficient thermal management, energy conservation, and emission reduction. However, the existing polymer foams still have some performance limitations and cannot meet the application demands in a wider range of situations. Accordingly, herein, an innovative strategy based on polyvinylidene fluoride (PVDF) melt blending and CO2 microcellular foaming was proposed for the fabrication of lightweight high-performance polymethylmethacrylate (PMMA) foams for heat insulation, and ultralight, tough, and hydrophobic foams with outstanding heat insulation and shape memory performances were successfully prepared. Because of the plasticization of PVDF and nucleation of PVDF microcrystals, the foaming temperature window of PMMA substantially descended, and the cellular structure of PMMA became refined. Blend foams with expansion ratios of 36.2, cell sizes of 15.8 μm, and foam densities of 0.0357 g∙cm−3 were obtained at 130 °C. Due to higher porosity and strong infrared absorption ability of PMMA, the resulting foams exhibited thermal conductivities of less than 32 mW∙m−1∙K−1. Owing to the hydrophobicity and incombustibility of PVDF and its microcrystals, the blend foams demonstrated better hydrophobicities, shape memory properties, and flame retardancies. This study provides an effective way for the green and mass production of high-performance polymer foams with appropriate thermal insulation performances.