CN103408845A

CN103408845A - EPDM (Ethylene-Propylene-Diene Monomer) foamed material with high-foaming ratio and foaming forming method thereof

Info

Publication number: CN103408845A
Application number: CN2013102933441A
Authority: CN
Inventors: 廖华勇
Original assignee: Changzhou University
Current assignee: Rudong Wenyuan investment and Development Co., Ltd
Priority date: 2013-07-12
Filing date: 2013-07-12
Publication date: 2013-11-27
Anticipated expiration: 2033-07-12
Also published as: CN103408845B

Abstract

The invention relates to an ethylene-propylene-diene monomer, and particularly relates to an EPDM (Ethylene-Propylene-Diene Monomer) foamed material with a high-foaming ratio and a foaming forming method thereof. The foaming forming method comprises the following steps of: according to proportioning of raw materials, plasticating the EPDM base material in an open mill, adding an additive to the base material in a plasticating process, after uniformly mixing the additive and the base material, taking down a mixture tablet and flattening the mixture tablet when the mixture tablet is hot; performing the mixture tablet, then placing the mixture tablet in a mold, carrying out foaming treatment, after ending foaming, cooling the mixture, and finally taking down a mold, thus obtaining the foaming material. The EPDM foamed material prepared by the method according to a formula has the beneficial effects that the foaming ratio is relatively high and exceeds the foaming ratio of conventional materials by 700%, the highest foaming ratio is 870%, the foaming density and the mechanical property can be adjusted, and the cost of used samples is not increased, i.e., the cost-performance ratio is high.

Description

A kind of high foamability EPDM foam materials and foam forming method thereof

Technical field

The present invention relates to terpolymer EP rubber, relate in particular to a kind of high foamability terpolymer EP rubber (EPDM) foam materials and foam forming method thereof.

Background technology

Terpolymer EP rubber (EPDM) is the rubber formed by ethene, propylene and the 3rd a small amount of monomer copolymerization, on its main chain, formed by chemically stable stable hydrocarbon, just in side chain, contain unsaturated double-bond, nonpolarity substituting group in molecule, molecule inner injection can be low, and molecular chain keeps in wide temperature range flexible; Thereby have excellent chemical stability, and ageing resistance, chemical proofing, electrical insulating property, shock elasticity and low-temperature performance, and hot water resistance can wait; Terpolymer EP rubber (EPDM) foam materials has the performances such as excellent buffering, sealing, heat insulation, sound insulation, can be applicable to the fields such as building, communications and transportation, packing; Current industrial EPDM frostproof froth n. multiplying power generally is up to 700%, and the expansion ratio of the EPDM foam materials prepared than prior art the present invention is higher.

Summary of the invention

Technical problem to be solved by this invention is:

Industrial EPDM frostproof froth n. multiplying power generally is up to 700%, and EPDM frostproof froth n. multiplying power prepared by the present invention is higher, the highlyest can reach 870%.

For solving this technical problem, the technical solution used in the present invention is:

The invention provides a kind of high foamability EPDM foam material, its raw material forms, and counts by weight:

100 parts of EPDM;

Linking agent 0.5-1 part;

Ac whipping agent 4-10 part;

Zinc oxide 1-5 part;

Stearic acid 0.5-1 part.

Foamed time 5-15min, blow(ing) pressure: 0-10MPa, blowing temperature: 150-180 ℃.

Optimum formula and technique EPDM 100, AC, 6; Linking agent 0.5, zinc oxide 2, stearic acid 1,170 ℃ of blowing temperatures, pressure 5MPa, foamed time 12min.

Wherein, selected EPDM mooney viscosity 42, iodine number 12, ethylene content 52%.

As preferably: linking agent is selected from dicumyl peroxide DCP or benzoyl peroxide BPO.

The present invention also provides a kind of preparation method of above-mentioned EPDM foam material, and concrete operations are:

(1) by the proportioning of each raw material, the EPDM base-material is plasticated in mill, in the process of plasticating, add auxiliary agent in base-material, auxiliary agent, with after base-material mixes, takes off the compound tablet, while hot pressing.

As preferably: in the process of plasticating, the roller temperature of two roller mills is made as in 45-60 ℃ of scope.

To the auxiliary agent added in base-material, just refer to after adding simultaneously linking agent, zinc oxide, stearic acid and add again the Ac whipping agent, in mixing process, play the triangle bag 5-7 time, until blend composition mixes.

Two roller mills are when plasticating, and roll spacing is made as 1mm, and during blanking, roll spacing tunes up to 3mm.

(2) by after the compound tablet premolding in step (1), the compound tablet is placed in mould, foaming is processed, and after having foamed, after material to be mixed was cooling, mold removal, obtained foam material.

As preferably: premolding is operating as, the compound tablet in 70 ℃ framed, premolding 10min under 5MPa pressure,

At this temperature, the HDPE/LDPE blend composition can melting not foaming again.

As preferably: foaming is treated to, and the compound tablet is in electric heating constant-temperature blowing drying box, and 5-10min foams at 160～180 ℃ of temperature.

As preferably: foaming is treated to, the compound tablet in vulcanizing press, under 160～180 ℃ of temperature and pressure 1～10MPa, foaming 10-15min.

When this temperature range can guarantee the foaming of EPDM material, melt strength was better, and foaming process and material cross-linking process can mate, pressure range and foamed time, value is the most reasonable in this scope, pressure improves again, little for the foaming material performance impact, waste power; Time increases again, and little for the foaming material performance impact, the increase time is reduced working efficiency, the waste energy.

The invention has the beneficial effects as follows: the EPDM frostproof froth n. multiplying power prepared according to formula of the present invention and technique is higher, surpass 700% of routine, make expansion ratio be up to 870%, foam density and mechanical property are adjustable, and the sample cost used does not increase, namely cost performance is high.

The accompanying drawing explanation

Fig. 1 is foam process schema of the present invention;

Fig. 2 is the blending foaming material of preparation in embodiment 1, the electron-microscope scanning figure (SEM) of foam after the liquid nitrogen freezing brittle failure;

Fig. 3 is the blending foaming material of preparation in embodiment 2, the electron-microscope scanning figure (SEM) of foam after the liquid nitrogen freezing brittle failure;

Fig. 4 is the blending foaming material of preparation in embodiment 3, the electron-microscope scanning figure (SEM) of foam after the liquid nitrogen freezing brittle failure.

Embodiment

In following examples, the umber related to is weight part.The raw material used and the particular case of equipment, as shown in Table 10 and Table 11:

Table 10 main raw material

Table 11 major equipment

Figure 2013102933441100002DEST_PATH_IMAGE002

Embodiment 1:

Foaming formulation is: 100 parts of EPDM, 0.5 part of benzoyl peroxide (BPO), 6 parts of Ac whipping agents, 3 parts, zinc oxide, 1 part of stearic acid.

Operation:

(1) the EPDM base-material is plasticated in mill, the roller temperature is 60 ℃, adds other auxiliary agent, finally adds whipping agent, plays the triangle bag 5 times, until blend composition mixes, tablet is taken off, and flattens while hot;

(2) by the tablet in step (1) framed middle through vulcanizing press premolding, pressure 5MPa, temperature 70 C, premolding 10min;

(3) then the tablet of precompressed is placed in mould and foams, under 160 ℃ of blowing temperatures and pressure 5MPa, foaming 10min.After having foamed, after foam material is cooling, from mould, taking off.

After testing: the blending foaming material apparent density is 0.139 g.cm ^-3, tear strength is 3.46 N/mm, tensile strength is 0.42 MPa, elongation at break 434%, your the A type hardness tester 4.2 that continues, expansion ratio 820%.

Density is pressed GB/T 6342) 1995 tests; Tear strength is pressed GB/T 529) in 1999, without scarfing angle tear strength standard, test; Tensile strength is pressed GB/T 528) 1998 tests.

Foam material is after the liquid nitrogen freezing brittle failure, and the electron-microscope scanning figure of foam is shown in shown in accompanying drawing 2, is found out by Fig. 2, and abscess-size, between 100 ~ 300 microns, is closed pore substantially.

Embodiment 2:

Operation:

(1) the EPDM base-material is plasticated in mill, the roller temperature is 60 ℃, adds other auxiliary agent, finally adds whipping agent, plays the triangle bag 5 times, until blend composition mixes, tablet is taken off, and flattens while hot.

(2) by the tablet in step (1) framed middle through vulcanizing press premolding, pressure 5MPa, temperature 70 C, premolding 10min.

(3) then the tablet of precompressed is placed in mould and foams, under 160 ℃ of blowing temperatures and pressure 5MPa, foaming 5min, after having foamed, after foam material is cooling, from mould, taking off.

After testing: the blending foaming material apparent density is 0.145 g.cm ^-3, tear strength is 3.59 N/mm, tensile strength is 0.51 MPa, elongation at break 356%, your the A type hardness tester 4.5 that continues, expansion ratio 760%.

Foam material is after the liquid nitrogen freezing brittle failure, the electron-microscope scanning figure of foam is shown in shown in accompanying drawing 3, by Fig. 3, found out, substantially be closed pore, abscess-size is more at the abscess below 100 microns, and also there are some abscess-sizes to surpass 100 microns and even reach 400 microns, be because foamed time is inadequate, whipping agent decomposes not exclusively, foams insufficient.

Embodiment 3:

Operation:

(3) then the tablet of precompressed is placed in mould and foams, under 160 ℃ of blowing temperatures and pressure 5MPa, foaming 12min, after having foamed, after foam material is cooling, from mould, taking off.

After testing: the blending foaming material apparent density is 0.124 g.cm-3, and tear strength is 3.21 N/mm, and tensile strength is 0.40 MPa, elongation at break 486%, your the A type hardness tester 3.9 that continues, expansion ratio 820.

Foam material is after the liquid nitrogen freezing brittle failure, and the electron-microscope scanning figure of foam is shown in shown in accompanying drawing 4, is found out by Fig. 4, and abscess-size more than 100 microns, is closed pore substantially substantially, and foamed time is enough, and whipping agent decomposes fully, and foaming fully.

Table 1 is done the formula (unit: mass parts) of variable for whipping agent;

Table 2 be foam material foam density, tensile strength, elongation at break, tear strength, your A type hardness tester and the expansion ratio variation diagram with the Ac foaming agent consumption continues;

Table 3 is formula (units: mass parts) that the BPO consumption is done variable;

Table 4 means the impact of BPO consumption on EPDM foam plastic density, tensile strength, elongation at break, tear strength, continue that A type hardness tester and expansion ratio;

Table 5 is formula (units: mass parts) that ZnO does variable;

Table 6 means the impact of ZnO consumption on EPDM foam plastic density, tensile strength, elongation at break, tear strength, continue that A type hardness tester and expansion ratio;

Table 7 means the impact of mold temperature on EPDM foam plastic density, tensile strength, elongation at break, tear strength, continue that A type hardness tester and expansion ratio;

Table 8 means the impact of forming pressure on EPDM foam plastic density, tensile strength, elongation at break, tear strength, continue that A type hardness tester and expansion ratio;

Table 9 means the impact of molding time on EPDM foam plastic density, tensile strength, elongation at break, tear strength, continue that A type hardness tester and expansion ratio.

Table 1 whipping agent is done the formula (unit: mass parts) of variable

Figure 2013102933441100002DEST_PATH_IMAGE003

Annotate: in the Ben Biaoge experiment, choose without exception mold temperature: 160 ℃, forming pressure: 5MPa, foamed time 10min.

The impact of table 2 AC foaming agent consumption on EPDM porous plastics performance

Table 3 BPO consumption is done the formula (unit: mass parts) of variable

The impact of table 4 BPO consumption on EPDM porous plastics performance

Figure 2013102933441100002DEST_PATH_IMAGE006

Table 5 ZnO does the formula (unit: mass parts) of variable

Figure 2013102933441100002DEST_PATH_IMAGE007

The impact of table 6 ZnO consumption on EPDM porous plastics performance

Figure 2013102933441100002DEST_PATH_IMAGE008

The impact of table 7 mold temperature on EPDM porous plastics performance

Annotate: in this experiment, choose without exception forming pressure: 5MPa, molding time: 10min; Same formula (weight part): EPDM 100, and ZnO 3, and BPO 0.5, AC whipping agent 6, stearic acid 1.

The impact of table 8 forming pressure on EPDM porous plastics performance

Figure 2013102933441100002DEST_PATH_IMAGE010

Annotate: in this experiment, choose without exception mold temperature: 160 ℃, molding time: 10min; Same formula (weight part): EPDM 100, and ZnO 3, and BPO 0.5, AC whipping agent 6, stearic acid 1.

The impact of table 9 molding time on EPDM porous plastics performance

Annotate: in experiment, choose without exception forming pressure: 5MPa, mold temperature: 160 ℃; Same formula: EPDM 100, ZnO 3, BPO 0.5, AC whipping agent 6, stearic acid 1(mass parts).

Claims

1. high foamability EPDM foam material is characterized in that: raw material forms, and counts by weight:

100 parts of EPDM;

Linking agent 0.5-1 part;

Ac whipping agent 4-10 part;

Zinc oxide 1-5 part;

Stearic acid 0.5-1 part.

2. a kind of high foamability EPDM foam material as claimed in claim 1, is characterized in that: 100 parts of EPDM, AC6 part; 0.5 part of linking agent, 2 parts, zinc oxide, 1 part of stearic acid.

3. a kind of high foamability EPDM foam material as claimed in claim 1, is characterized in that: described EPDM mooney viscosity 42, iodine number 12, ethylene content 52%.

4. a kind of high foamability EPDM foam material as claimed in claim 1, it is characterized in that: linking agent is selected from dicumyl peroxide DCP or benzoyl peroxide BPO.

5. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 1, is characterized in that comprising the steps:

(1) by the proportioning of each raw material, the EPDM base-material is plasticated in mill, in the process of plasticating, add auxiliary agent in base-material, auxiliary agent, with after base-material mixes, takes off the compound tablet, while hot pressing;

6. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 5, it is characterized in that: in the described process of plasticating, the roller temperature of two roller mills is made as in 45-60 ℃ of scope; Described auxiliary agent to adding in base-material, just refer to after adding simultaneously linking agent, zinc oxide, stearic acid and add the Ac whipping agent again, in mixing process, plays the triangle bag 5-7 time, until blend composition mixes; Two roller mills are when plasticating, and roll spacing is made as 1mm, and during blanking, roll spacing tunes up to 3mm.

7. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 5, it is characterized in that: described premolding is operating as: the compound tablet is in 70 ℃ framed, premolding 10min under 5MPa pressure, at this temperature, the HDPE/LDPE blend composition can melting not foaming again.

8. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 5, it is characterized in that: described foaming is treated to: foamed time 5-15min, blow(ing) pressure: 0-10MPa, blowing temperature: 150-180 ℃.

9. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 8, it is characterized in that: described foaming is treated to: the compound tablet is in electric heating constant-temperature blowing drying box, and 5-10min foams at 160～180 ℃ of temperature; Or the compound tablet is in vulcanizing press, under 160～180 ℃ of temperature and pressure 1～10MPa, foaming 10-15min.

10. the preparation method of a kind of high foamability EPDM foam material as claimed in claim 9, it is characterized in that: described foaming is treated to: the compound tablet in vulcanizing press, 170 ℃ of blowing temperatures, pressure 5MPa, foamed time 12min.