Branched, cross-linked, intumescent, anti-droplet flame-retardant copolyester based on triazine ring structure and preparation method thereof

Abstract

The invention discloses branching, cross-linking, expanded, melt-dropping-resistant and flame-retardant copolyester based on a triazine ring structure. The copolyester is prepared by conducting random copolymerization on structure units expressed as formulae I, II and III or structure units expressed as formulae I, II, III and IV according to a conventional method. The intrinsic viscosity [eta] of the prepared branching, cross-linking, expanded, melt-dropping-resistant and flame-retardant copolyester is 0.41-1.10 dL / g; the extreme oxygen index is 24.5-38.0%; the vertical combustion grade is between V-2 and V-0; the peak heat release rate p-HRR in a cone heat test is 247-643 kW / m<2>. According to the copolyester, a modified monomer of the triazine ring structure is introduced, and then copolymerized with polyester to form a unique ternary branched cross-linking network structure; the modified monomer of the triazine ring structure contains the flame-retardant element nitrogen, so that the melt viscosity of the copolyester in combustion can be improved; the copolyester is capable of releasing nitrogen and quickly forming an expanded char layer with excellent heat and oxygen insulation effects; especially, a phosphorus-nitrogen synergism effect can be generated when the copolyester is used together with the conventional phosphorus-containing flame-retardant agent; the flame-retardant performance and the melt-dropping-resistant effects can be more excellent; the selected monomer is low in price; the preparation process is mature; the operation is simple and convenient; the industrialized large-scale production is liable to implement.

Description

technical field

[0001] The invention belongs to the technical field of anti-droplet copolyester and its preparation. Specifically, the present invention relates to a kind of copolyester with branched cross-linking, expansion flame retardancy and anti-dropping property and its preparation method. This type of copolyester can use monomers containing triazine ring structural units alone. Through its unique nitrogen-containing ring branched structure, the melt viscosity of the copolyester can be increased at high temperature, and it can be promoted to form a unique microstructure at high temperature. The expanded carbon layer of the structure can insulate heat, so that it can obtain flame retardant properties and a certain anti-droplet performance; it is also possible to use phosphorus-containing flame-retardant monomers to work together with monomers containing triazine ring structural units to form an efficient "phosphorus Nitrogen synergy" effect allows copolyester to obtain b...

Examples

Embodiment 1

[0053] 860g of terephthalic acid, 435mL of ethylene glycol, 4.5g of tris(2-hydroxyethyl)isocyanurate and 0.503g of tetrabutyl titanate were added to the reaction kettle, filled with nitrogen to remove the air in the kettle, and pressurized to 0.1MPa; within 2 hours, the temperature was raised to 240°C to start the esterification reaction, and the pressure in the kettle was controlled to be 0.3-0.4MPa. After maintaining for 2 hours, the pressure began to decrease. After 1.5 hours, the temperature gradually rose to 260°C, and the pressure dropped to normal pressure. The esterification reaction is completed; thereafter, the polycondensation reaction is carried out at 260-270°C for 0.5h in a low vacuum, and then the temperature is raised to 280°C in a high vacuum (pressure <60Pa) and the polycondensation reaction is carried out for 0.5-1 hour.

[0054] The intrinsic viscosity of the copolyester is 0.84dL / g; the oxygen index is 24.5%; the vertical combustion rating is V-2; the peak ...

Embodiment 2

[0056] 860g terephthalic acid, 425mL ethylene glycol, 27.0g tris (2-hydroxyethyl) isocyanurate and 0.510g tetrabutyl titanate were added to the reactor, and the steps given in Example 1 and After the esterification and polycondensation reactions are carried out under the conditions, the material is discharged.

[0057] The intrinsic viscosity of the copolyester is 0.79dL / g; the oxygen index is 26.0%; the vertical combustion rating is V-2; the peak heat release rate pHRR in the cone calorimetry test is 535kW / m 2 .

Embodiment 3

[0059] 860g of terephthalic acid, 418mL of ethylene glycol, 45.0g of three (2-hydroxyethyl) isocyanurate and 0.501g of tetrabutyl titanate were added to the reaction kettle, and the steps given in Example 1 and After the esterification and polycondensation reactions are carried out under the conditions, the material is discharged.

[0060] The intrinsic viscosity of the copolyester is 0.77dL / g; the oxygen index is 28.0%; the vertical combustion rating is V-2; the peak heat release rate pHRR in the cone calorimetry test is 473kW / m 2 .

technical field

[0001] The invention belongs to the technical field of anti-droplet copolyester and its preparation. Specifically, the present invention relates to a kind of copolyester with branched cross-linking, expansion flame retardancy and anti-dropping property and its preparation method. This type of copolyester can use monomers containing triazine ring structural units alone. Through its unique nitrogen-containing ring branched structure, the melt viscosity of the copolyester can be increased at high temperature, and it can be promoted to form a unique microstructure at high temperature. The expanded carbon layer of the structure can insulate heat, so that it can obtain flame retardant properties and a certain anti-droplet performance; it is also possible to use phosphorus-containing flame-retardant monomers to work together with monomers containing triazine ring structural units to form an efficient "phosphorus Nitrogen synergy" effect allows copolyester to obtain b...

Examples

Embodiment 1

[0053] 860g of terephthalic acid, 435mL of ethylene glycol, 4.5g of tris(2-hydroxyethyl)isocyanurate and 0.503g of tetrabutyl titanate were added to the reaction kettle, filled with nitrogen to remove the air in the kettle, and pressurized to 0.1MPa; within 2 hours, the temperature was raised to 240°C to start the esterification reaction, and the pressure in the kettle was controlled to be 0.3-0.4MPa. After maintaining for 2 hours, the pressure began to decrease. After 1.5 hours, the temperature gradually rose to 260°C, and the pressure dropped to normal pressure. The esterification reaction is completed; thereafter, the polycondensation reaction is carried out at 260-270°C for 0.5h in a low vacuum, and then the temperature is raised to 280°C in a high vacuum (pressure <60Pa) and the polycondensation reaction is carried out for 0.5-1 hour.

[0054] The intrinsic viscosity of the copolyester is 0.84dL / g; the oxygen index is 24.5%; the vertical combustion rating is V-2; the peak ...

Embodiment 2

[0056] 860g terephthalic acid, 425mL ethylene glycol, 27.0g tris (2-hydroxyethyl) isocyanurate and 0.510g tetrabutyl titanate were added to the reactor, and the steps given in Example 1 and After the esterification and polycondensation reactions are carried out under the conditions, the material is discharged.

[0057] The intrinsic viscosity of the copolyester is 0.79dL / g; the oxygen index is 26.0%; the vertical combustion rating is V-2; the peak heat release rate pHRR in the cone calorimetry test is 535kW / m 2 .

Embodiment 3

[0059] 860g of terephthalic acid, 418mL of ethylene glycol, 45.0g of three (2-hydroxyethyl) isocyanurate and 0.501g of tetrabutyl titanate were added to the reaction kettle, and the steps given in Example 1 and After the esterification and polycondensation reactions are carried out under the conditions, the material is discharged.

[0060] The intrinsic viscosity of the copolyester is 0.77dL / g; the oxygen index is 28.0%; the vertical combustion rating is V-2; the peak heat release rate pHRR in the cone calorimetry test is 473kW / m 2 .

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