Temperature-sensitive response shape memory foam material with shock absorption function and preparation method and application thereof
阅读说明：本技术 兼具减震功能的温敏响应形状记忆发泡材料及其制备方法和应用 (Temperature-sensitive response shape memory foam material with shock absorption function and preparation method and application thereof ) 是由 林鸿飞 蔡志杰 于 2021-07-02 设计创作，主要内容包括：本发明涉及一种兼具减震功能的温敏响应形状记忆发泡材料,由如下重量份数计的组分发泡制成：10-40份反式-1,4-聚异戊二烯橡胶、0-10份富含乙烯支化的苯乙烯嵌段共聚物、10-20份丙烯-4-甲基戊烯共聚物、EVA、POE、滑石粉、过氧化物交联剂、发泡剂、氧化锌、硬脂酸、硬脂酸锌。本发明在EVA和POE基础材料中引入了丙烯-4-甲基戊烯共聚物、反式-1,4-聚异戊二烯橡胶,尤其是在其中进一步引入富含乙烯支化的苯乙烯嵌段共聚物,能够与丙烯-4-甲基戊烯共聚物、反式-1,4-聚异戊二烯橡胶及其他组分协同增强,共同提高室温形状固定率、形状回复率和循环使用次数,同时增强减震性能,可以快速实现私人定制产品,周期短、效率高、可重复性、性价比高。(The invention relates to a temperature-sensitive response shape memory foam material with a shock absorption function, which is prepared by foaming the following components in parts by weight: 10-40 parts of trans-1, 4-polyisoprene rubber, 0-10 parts of styrene block copolymer rich in ethylene branching, 10-20 parts of propylene-4-methylpentene copolymer, EVA, POE, talcum powder, peroxide crosslinking agent, foaming agent, zinc oxide, stearic acid and zinc stearate. According to the invention, the propylene-4-methylpentene copolymer and the trans-1, 4-polyisoprene rubber are introduced into the EVA and POE base materials, particularly the styrene block copolymer rich in ethylene branching is further introduced, and the ethylene block copolymer, the propylene-4-methylpentene copolymer, the trans-1, 4-polyisoprene rubber and other components can be synergistically enhanced, so that the shape fixing rate, the shape recovery rate and the cycle use frequency at room temperature are improved, the damping performance is enhanced, a private customized product can be rapidly realized, and the EVA and POE base materials have the advantages of short period, high efficiency, repeatability and high cost performance.)
1. The temperature-sensitive response shape memory foam material with the shock absorption function is characterized by being prepared by foaming the following components in parts by weight: 10-40 parts of trans-1, 4-polyisoprene rubber, 30-50 parts of EVA (ethylene vinyl acetate), 10-20 parts of POE (polyolefin elastomer), 0-10 parts of an ethylene-rich branched styrene block copolymer, 10-20 parts of a propylene-4-methylpentene copolymer, 5-15 parts of talcum powder, 0.4-0.6 part of a peroxide crosslinking agent, 2-3 parts of a foaming agent, 1-2 parts of zinc oxide, 0.4-0.6 part of stearic acid and 0.8-1.0 part of zinc stearate.
2. The temperature-sensitive responsive shape memory foam material with a shock-absorbing function according to claim 1, wherein: the ethylene-rich branched styrene block copolymer is SIS or SEBS.
3. The temperature-sensitive responsive shape memory foam material with a shock-absorbing function according to claim 1, wherein: the styrene block molar content of the ethylene-rich branched styrene block copolymer is < 25%.
4. The temperature-sensitive responsive shape memory foam material with a shock-absorbing function according to claim 1, wherein: the VA molar content of the EVA is 20-40%.
5. The temperature-sensitive responsive shape memory foam material with a shock-absorbing function according to claim 1, wherein: the hardness of the POE is less than 82A, and the crystallinity is less than 20%.
6. The temperature-sensitive responsive shape memory foam material with a shock-absorbing function according to claim 1, wherein: the foaming agent is selected from one or more of azodicarbonamide, N' -dinitrosopentamethylenetetramine, expanded microspheres and 4, 4-oxo-diphenyl sulfonyl hydrazide.
7. A preparation method of the temperature-sensitive response shape memory foam material with the shock absorption function according to any one of claims 1 to 6, which is characterized by comprising the following steps:
s1, weighing: according to the formula, talcum powder, zinc oxide, stearic acid and zinc stearate are prepared into a material B, a peroxide cross-linking agent and a foaming agent are prepared into a material C, and the rest components are prepared into a material A;
s2, banburying: when the temperature of the machine is increased to 90 +/-5 ℃, the material A is poured into an internal mixer, the machine is opened for internal mixing, and the material B is poured when the temperature is increased to 110 +/-5 ℃; when the temperature is raised to 120 +/-5 ℃, pouring the material C, mixing for 4-6 min, and pouring out the mixed material to obtain a material M;
s3, open mixing: setting the temperature of a roller of the open mill to be 70 +/-5 ℃, starting a roller table after the temperature is reached, putting the M material subjected to internal mixing into the open mill, controlling the sheet outlet temperature to be below 70 ℃, and controlling the sheet outlet thickness to be 3-5 mm;
s4, hot-pressing foaming: and putting the mixed sheet into a large molding foaming mold to complete vulcanization foaming.
8. The method for preparing the temperature-sensitive response shape memory foam material with the shock absorption function according to claim 7, wherein the method comprises the following steps: the banburying time of the step S2 is controlled to be 600 +/-60 seconds, and the banburying discharging temperature is 120 +/-5 ℃.
9. Temperature-sensitive responsive shape with shock-absorbing function according to claim 7The preparation method of the memory foam material is characterized by comprising the following steps: the foaming pressure of step S4: 160kg/cm2～180kg/cm2The foaming temperature: 170 +/-5 ℃ and the foaming time is calculated by multiplying the thickness of the die by 100 +/-10 s/mm.
10. Use of the temperature-sensitive response shape memory foam material with a shock absorption function as claimed in any one of claims 1 to 6 in insoles, cushions or pillows.
Technical Field
The invention belongs to the technical field of memory materials, and particularly relates to a temperature-sensitive response shape memory foam material with a shock absorption function, and a preparation method and application thereof.
Background
With the improvement of living standard of people and the situation that the material consumption is greatly met, people pay more attention to the physical health of people, so higher requirements are put forward to the consumption requirements of the materials, and personalized private customization comes from this.
The existing insoles, cushions, back cushions and pillows in the market are generally public, but the foot shapes, the hip shapes, the backs and the head shapes of all people are different, so that the contradiction of meeting the exclusive customization requirements of consumers according to different people is increasingly prominent. With the rapid development of electronic commerce, private exclusive customization in an internet mode is developed vigorously, and although individual requirements are met to a great extent and individuality is reflected, the problems of long customization period and high cost exist. Therefore, there is a need for a personal subscription that has a high cost-performance that can be quickly implemented.
In addition, the shock absorption performance of the high polymer is closely related to the viscoelasticity of the polymer, the deformation of the polymer near the glass transition (Tg) is mainly generated by chain segment movement, the chain segment movement is under the action of internal friction resistance, the chain segment movement cannot follow the change of stress under the action of alternating stress, and the macroscopic expression shows that the strain lags behind the stress, namely, a hysteresis phenomenon exists. In each cycle, internal dissipation occurs when mechanical dissipation takes place and energy is consumed. This hysteresis internal loss due to internal friction is the ability to convert mechanical energy into thermal energy, referred to as the damping performance capability of the material.
The memory principle of the temperature-sensitive response shape memory foaming material is as follows: mixing and granulating a polymer material and various compounding agents, then carrying out cross-linking foaming reaction in a mould and determining a primary shape, and cooling and crystallizing to obtain an initial state, wherein a chemical cross-linking structure of the initial state is a stationary phase, and a crystalline phase is a reversible phase. When the temperature is increased to be higher than the melting point (Tm), the reversible phase is melted and softened, can be made into any shape under the action of external force, keeps external force, is cooled and fixed, and enables the molecular chain to be directionally frozen along the direction of the external force to obtain the deformed shape. When the temperature is increased to be higher than Tm, the reversible phase molecular chain is naturally curled under the action of entropy elasticity until reaching a thermodynamic equilibrium state, so that shape recovery occurs, and the reversible cycle is realized in the shape memory process.
In the temperature response shape memory materials in the patent, ethylene-vinyl acetate copolymer (EVA) with high VA content has the problems of low room temperature deformation fixing rate and high thermal stimulation temperature (more than or equal to 75 ℃) due to slightly low crystallinity; trans-1, 4-polyisoprene rubber (TPI), the thermal stimulation temperature is low, but the single use is not suitable for crosslinking foaming and contains a large amount of unsaturated double bonds and is easy to age; the ethylene-rich branched styrene block copolymer and the propylene and 4-methylpentene copolymer with substituent in the molecular chain have good shock absorbing performance and poor resilience.
Disclosure of Invention
The invention aims to provide a temperature-sensitive response shape memory foam material with a shock absorption function, a preparation method and application thereof, and the foam material has the advantages of low thermal stimulation response temperature, moderate deformation rate, high room-temperature deformation fixation rate and deformation recovery rate, and good shock absorption performance.
In order to achieve the purpose, the invention adopts the technical scheme that:
the temperature-sensitive response shape memory foam material with the shock absorption function is prepared by foaming the following components in parts by weight: 10-40 parts of trans-1, 4-polyisoprene rubber, 30-50 parts of EVA (ethylene vinyl acetate), 10-20 parts of POE (polyolefin elastomer), 0-10 parts of an ethylene-rich branched styrene block copolymer, 10-20 parts of a propylene-4-methylpentene copolymer, 5-15 parts of talcum powder, 0.4-0.6 part of a peroxide crosslinking agent, 2-3 parts of a foaming agent, 1-2 parts of zinc oxide, 0.4-0.6 part of stearic acid and 0.8-1.0 part of zinc stearate.
Preferably, the ethylene-rich branched styrene block copolymer is SIS or SEBS.
Preferably, the styrene block molar content in the ethylene-rich branched styrene block copolymer is < 25%.
Preferably, the VA molar content of the EVA is 20-40%.
Preferably, the POE has hardness < 82A and crystallinity < 20%.
Preferably, the peroxide crosslinking agent is selected from dicumyl peroxide and/or 1, 4-di-tert-butylperoxyisopropyl benzene.
Preferably, the foaming agent is selected from one or more of azodicarbonamide, N' -dinitrosopentamethylenetetramine, expanded microspheres, and 4, 4-oxydiphenylsulfonyl hydrazide.
The invention also provides a preparation method of the temperature-sensitive response shape memory foam material with the shock absorption function, which comprises the following steps:
s1, weighing: according to the formula, talcum powder, zinc oxide, stearic acid and zinc stearate are prepared into a material B, a peroxide cross-linking agent and a foaming agent are prepared into a material C, and the rest components are prepared into a material A;
s2, banburying: when the temperature of the machine is increased to 90 +/-5 ℃, the material A is poured into an internal mixer, the machine is opened for internal mixing, and the material B is poured when the temperature is increased to 110 +/-5 ℃; when the temperature is raised to 120 +/-5 ℃, pouring the material C, mixing for 4-6 min, and pouring out the mixed material to obtain a material M;
s3, open mixing: setting the temperature of a roller of the open mill to be 70 +/-5 ℃, starting a roller table after the temperature is reached, putting the M material subjected to internal mixing into the open mill, controlling the sheet outlet temperature to be below 70 ℃, and controlling the sheet outlet thickness to be 3-5 mm;
s4, hot-pressing foaming: and putting the mixed sheet into a large molding foaming mold to complete vulcanization foaming.
Preferably, the banburying time of the step S2 is controlled to be 600 +/-60 seconds, and the banburying discharging temperature is 120 +/-5 ℃.
Preferably, the foaming pressure of step S4 is: 160kg/cm2～180kg/cm2The foaming temperature: 170 +/-5 ℃ and foaming time of 100 +/-10 s multiplied by the thickness of the dieAnd calculating the/mm.
The invention further provides application of the temperature-sensitive response shape memory foam material with the shock absorption function in insoles, cushions, back cushions or pillows.
Compared with the prior art, the invention has the following beneficial effects:
the invention introduces the propylene-4-methylpentene copolymer and the trans-1, 4-polyisoprene rubber into the EVA and POE base materials, can be simply and rapidly deformed, has adjustable deformation rate and high room temperature shape fixing rate and recovery rate, particularly introduces the styrene block copolymer rich in ethylene branching, can be synergistically enhanced with the propylene-4-methylpentene copolymer, the trans-1, 4-polyisoprene rubber and other components, jointly improves the room temperature shape fixing rate, the shape recovery rate and the cycle use times, simultaneously enhances the shock absorption performance, can rapidly realize private customized products (pillows, cushions, insoles, footbeds, cushions and the like), and has short period, high efficiency, repeatability and high cost performance.
Detailed Description
The invention provides a temperature-sensitive response shape memory foam material with a shock absorption function, which is prepared by foaming the following components in parts by weight: 10-40 parts of trans-1, 4-polyisoprene rubber, 30-50 parts of EVA (ethylene vinyl acetate), 10-20 parts of POE (polyolefin elastomer), 0-10 parts of styrene block copolymer rich in ethylene branching, 10-20 parts of propylene-4-methylpentene copolymer, 5-15 parts of talcum powder, 0.4-0.6 part of peroxide cross-linking agent, 2-3 parts of foaming agent, 1-2 parts of zinc oxide, 0.4-0.6 part of stearic acid and 0.8-1.0 part of stearic acid
And (3) zinc stearate.
The melting point of trans-1, 4-polyisoprene rubber is less than 70 deg.C, and Kuraray TP-301 (melting point 67 deg.C, hardness 78A, crystallinity 36%, manufactured by Kuraray, Japan) can be used as the trade name.
The EVA has a VA molar content of 20-40%, and can be selected from EVA 7360 (21% VA molar content, 86A hardness, 80 ℃ melting point, 48 ℃ softening temperature, 32.2% crystallinity, Taitai plastic company), EVA 6110M (26% VA molar content, 82A hardness, 76 ℃ melting point, 43 ℃ softening temperature, 24.8% crystallinity, Yangzhiba Limited liability company), EVA 3312 (33% VA molar content, 65A hardness, 64 ℃ melting point, 35 ℃ softening temperature, 14.5% crystallinity, Taiwan polymerization chemical company Limited).
The POE has hardness less than 82A and crystallinity less than 20%, and Fortify C0507D (hardness 74A, melting point 59 ℃, crystallinity 16%, Sauter basic industries Co., Ltd.) and Fortify C5070D (hardness 63A, melting point 62 ℃, crystallinity 16%, Sauter basic industries Co., Ltd.) are selected as trademarks.
Wherein said ethylene-rich branched styrene block copolymer is SIS or SEBS having a styrene block molar content of < 25%. Specifically, the method comprises the following steps: the SIS is selected from HYBRAR 5125 (styrene mol content 20%, hardness 60A, Nippon kokuraray) company), HYBRAR 5127 (styrene mol content 20%, hardness 84A, Nippon koraray) company); the SEBS is selected from SOE 1605 (hardness 87A, Asahi Kasei Co., Ltd.), SOE 1609 (hardness 87A, Asahi Kasei Co., Ltd.).
The propylene-4-methylpentene copolymer may be available in ABSORTOMER EP1001 (hardness 92A, Nippon Mitsui Kabushiki Kaisha) or ABSORTOMER EP1013 (hardness 69D, Nippon Mitsui Kabushiki Kabushi.
Wherein the peroxide crosslinking agent is selected from dicumyl peroxide and/or 1, 4-di-tert-butylperoxyisopropyl benzene. The foaming agent is selected from one or more of azodicarbonamide, N' -dinitrosopentamethylenetetramine, expanded microspheres and 4, 4-oxo-diphenyl sulfonyl hydrazide.
The invention provides examples 1-8 and comparative examples 1-4, formulation tables are shown in tables 1 and 2.
Table 1: formulation table of shape memory foam materials of examples 1 to 8 of the present invention (parts by weight)
Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
Example 8
TP-301
20
40
30
20
40
20
10
10
EVA 7360
_
_
50
_
20
_
_
_
EVA 6110M
40
_
_
40
_
40
_
_
EVA 3312
_
40
_
_
30
_
50
50
C0507D
_
10
_
_
10
20
_
_
C5070D
20
_
15
20
_
_
20
20
HYBRAR 5125
_
_
_
_
_
_
10
10
HYBRAR 5127
_
_
_
_
_
5
_
_
SOE 1605
_
_
_
10
_
_
_
5
SOE 1609
_
_
_
_
10
_
_
_
EP1001
20
10
20
_
20
10
10
EP1013
_
_
15
_
10
_
_
_
Talcum powder
10
8
12
10
15
10
10
10
BIBP 14S-FL
0.5
0.4
0.6
0.5
0.6
0.5
0.5
0.5
AC6000H
2.2
2.5
2
2.2
3
2.2
2.2
3
ZnO 997
1.5
2
2
1.5
1.5
1.5
1.5
1
Stearic acid SA1840
0.5
0.5
0.6
0.5
0.6
0.5
0.5
0.4
Zinc stearate
0.8
0.8
1.0
0.8
1.0
0.8
0.8
0.8
Table 2: formulation table of shape memory foam of comparative examples 1 to 4 of the present invention (parts by weight)
The shape memory foams of examples 1 to 8 and comparative examples 1 to 4 were prepared by the following method comprising the steps of: s1, weighing: according to the formula, talcum powder, zinc oxide, stearic acid and zinc stearate are prepared into a material B, a peroxide cross-linking agent and a foaming agent are prepared into a material C, and the rest components are prepared into a material A; s2, banburying: when the temperature of the machine is increased to 90 +/-5 ℃, the material A is poured into an internal mixer, the machine is opened for internal mixing, and the material B is poured when the temperature is increased to 110 +/-5 ℃; when the temperature rises to 120 +/-5 ℃, pouring the material C, mixing for 4-6 min, and then pouring out the mixed material to obtain a material M, wherein the banburying time is controlled at 600 +/-60 s, and the banburying discharging temperature is 120 +/-5 ℃; s3, open mixing: setting the temperature of a roller of the open mill to be 70 +/-5 ℃, starting a roller table after the temperature is reached, putting the M material subjected to internal mixing into the open mill, controlling the sheet outlet temperature to be below 70 ℃, and controlling the sheet outlet thickness to be 3-5 mm; s4, hot-pressing foaming: putting the mixed sheet into a large molding foaming mold to complete vulcanization foaming, wherein the foaming pressure is as follows: 160kg/cm2～180kg/cm2The foaming temperature: 170 +/-5 ℃ and the foaming time is calculated by multiplying the thickness of the die by 100 +/-10 s/mm.
The shape memory foams provided in examples 1 to 8 and comparative examples 1 to 4 were examined for their properties, and the results are shown in tables 3 and 4.
The Shore hardness A0 is tested according to GB/T531.1-2008 standard; the rebound resilience is tested in accordance with DIN 8307 standard.
Deformation rate test method-compression test method: cutting the prepared foaming sheet into test pieces of 10cm x 1cm (thickness L0), putting the test pieces into an oven at 75 ℃/65 ℃/55 ℃/45 ℃ for 10min, immediately taking out the test pieces, and then, statically pressing the test pieces for 10min by using an iron weight pressure head with the diameter of 3cm and the weight of 25kg, and recording the thickness L1 of the test pieces under a compressed state, wherein the deformation rate D is (L0-L1) 100%/L0;
the room temperature shape fixing rate test method comprises the following steps: the test piece after the compression test is placed in a constant temperature environment chamber at 23 ℃, and the thickness L2 of the test piece is recorded after 24 hours. Room-temperature shape fixation rate F ═ 100%/(L0-L1) of (L0-L2);
shape recovery test method: placing the test piece subjected to the deformation rate test into an oven at 75 ℃/65 ℃/55 ℃/45 ℃ for 10min, taking out the test piece, placing the test piece into a constant-temperature environment chamber at 23 ℃, and recording the thickness L3 of the test piece at the moment after 30min, wherein the shape recovery rate R is (L3-L1) × 100%/(L0-L1);
number of recyclable uses: placing a test piece of 15cm by 0.6cm (with the thickness of L0) into an oven at 60 ℃ for 10min, taking out the test piece, immediately carrying out static pressure on the test piece for 180min by using an iron weight pressure head with the diameter of 3cm and the weight of 25kg, then placing the test piece in a constant temperature environment at 23 ℃ for 48h, recording the thickness of the test piece L5, then placing the test piece into the oven at 60 ℃ for 10min, taking out the test piece, and then recording the thickness of the test piece L6, wherein the shape recovery rate K is (L6-L5)% 100%/(L0-L5) (K is more than or equal to 85%) and is defined as recyclable, and M < 85% is defined as non-recyclable. [ MEANS FOR solving PROBLEMS ] is provided. The number of times of repeated use is 1 after 1 cycle of the test, the cycle test is carried out according to the method until M is less than 85%, and the number of cycles at the moment is recorded as the number of times of repeated use.
Table 3: tables showing the results of the physical property tests of the foams of examples 1 to 8 of the present invention
Item
Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
Example 8
Hardness A0
32
36
30
26
32
30
22
28
The rebound resilience%
45
50
43
45
44
45
43
46
Deformation rate at 75%
63.5
61.5
62.1
65.2
65.6
66.1
64.1
64.5
Shape fixation ratio at room temperature%
93.5
94.8
94.5
96.6
97.1
96.8
93.6
94.2
Shape recovery at 75%
96.2
98.1
97.2
99.2
99.4
98.8
96.2
96.7
Deformation rate at 65%
58.4
57.3
58.6
62.2
62.5
61.8
61.2
61.8
Shape fixation ratio at room temperature%
94.8
94.9
94.2
96.2
96.3
95.8
95.1
95.2
Shape recovery at 65%
91.6
92.8
92.2
95.1
95.5
92.1
91.2
91.5
Deformation rate at 55%
33.2
31.3
32.6
35.6
37.1
36.2
34.8
35.1
Shape fixation ratio at room temperature%
96.0
96.2
95.6
98.6
98.8
98.4
95.3
95.5
Shape recovery at 55%
86.8
87.2
86.2
90.4
89.8
89.6
86.3
87.2
Deformation rate at 45%
2.7
1.6
2.2
4.2
3.8
3.7
3.1
3.5
Shape fixation ratio at room temperature%
97.2
98.8
97.6
98.8
98.2
98.6
97.5
98.1
45℃Shape recovery Rate%
60.8
62.8
61.4
63.6
63.5
63.1
59.8
61.2
Number of times of recycling
28
26
28
32
30
31
29
30
Table 4: tables showing the results of physical property tests of the foamed materials of comparative examples 1 to 4 of the present invention
From the above experiments, it can be known that the shape memory foam material of the present invention introduces the propylene-4-methylpentene copolymer and the trans-1, 4-polyisoprene rubber into the EVA and POE base materials, such that the EVA and the POE base materials can be easily and rapidly deformed, the deformation rate can be adjusted, and the room temperature shape fixing rate and recovery rate are high, and particularly, the ethylene-rich branched styrene block copolymer is further introduced into the shape memory foam material, such that the shape memory foam material can be synergistically enhanced with the propylene-4-methylpentene copolymer, the trans-1, 4-polyisoprene rubber and other components, such that the room temperature shape fixing rate, the shape recovery rate and the cycle use frequency are jointly improved, and the foam material is also provided with good damping performance.
While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be understood by those skilled in the art that the invention is not limited by the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.