EVA添加POE有哪些優缺點？

What Are the Advantages and Disadvantages of Adding POE to EVA?

PART 3

再加入SEBS改善物性，為何雙螺桿分散才是關鍵？

When SEBS Is Added to Improve Properties, Why Is Twin-Screw Dispersion the Key?

八、推薦加工路線：先造「聚合物母粒」，再做反應發泡

VIII. Recommended Processing Route: Make a Polymer Masterbatch First, Then Perform Reactive Foaming

原料規格化：確認EVA的VA含量與MFR、POE密度／熔融區間、SEBS苯乙烯含量／分子量／充油量。

Standardize raw-material specifications: Confirm the VA content and MFR of EVA, the density/melting range of POE, and the styrene content/molecular weight/oil loading of SEBS.

失重式計量：對SEBS、相容劑與油品使用穩定計量，避免體積餵料造成批次波動。

Loss-in-weight metering: Use stable gravimetric metering for SEBS, compatibilizers, and oils to avoid batch variation caused by volumetric feeding.

雙螺桿預混：先塑化EVA／POE，再導入SEBS；以捏合塊建立分散，以混合元件完成分布。

Twin-screw pre-compounding: Plasticize EVA/POE first, then introduce SEBS; use kneading blocks for dispersion and mixing elements for distribution.

真空與過濾：控制揮發分、未熔粒及污染物，再水冷／風冷造粒。

Vacuum and filtration: Control volatiles, unmelted particles, and contaminants, then pelletize with water or air cooling.

第二段低溫混煉：加入DCP、發泡劑、活化劑與其他熱敏助劑，嚴格限制實際料溫。

Second-stage low-temperature mixing: Add DCP, the blowing agent, activators, and other heat-sensitive additives while strictly limiting the actual compound temperature.

熟化與成型：統一母粒停放、含水與批次條件，再進行模壓／射出發泡。

Conditioning and molding: Standardize masterbatch aging, moisture, and batch conditions before compression or injection foaming.

一個實務上的螺桿配置思路

A Practical Approach to Screw Configuration

前段使用輸送元件建立穩定固體輸送；第一混煉區完成EVA／POE熔融；中段以中等角度捏合塊讓SEBS充分塑化並破碎團聚；後段使用分布混合元件降低相尺寸差，再經真空排氣與穩壓計量。若材料溫升過高，應優先調整捏合強度、充填度與冷卻，而不是只降低機筒設定溫度。

Use conveying elements in the front section to establish stable solids transport; melt EVA/POE in the first mixing zone; use medium-angle kneading blocks in the middle section to fully plasticize SEBS and break up agglomerates; and use distributive mixing elements in the rear section to narrow the domain-size distribution before vacuum venting and pressure-stabilized metering. If material temperature rises excessively, first adjust kneading intensity, fill level, and cooling instead of merely lowering the barrel setpoint.

為何不建議一次完成所有配方｜DCP與化學發泡劑具有溫度—時間累積效應。若在高剪切雙螺桿中與SEBS一起長時間混煉，可能提前分解、焦燒或消耗有效活性，使後續模壓時產氣與交聯時序失真。 Why completing the entire formulation in one step is not recommended | DCP and chemical blowing agents have cumulative temperature-time effects. Prolonged mixing with SEBS in a high-shear twin-screw extruder may cause premature decomposition or scorch, or consume effective activity, disrupting gas-generation and crosslinking timing during subsequent compression molding.

九、建議DOE：同時優化配方、分散與發泡窗口

IX. Recommended DOE: Optimize the Formulation, Dispersion, and Foaming Window Together

因子 Factor	建議水準 Recommended Levels	主要反應值 Primary Responses
POE比例 POE Proportion	低／中／高 Low/Medium/High	硬度、回彈、DSC、收縮 Hardness, resilience, DSC, and shrinkage
SEBS比例 SEBS Proportion	0／低／中 0/Low/Medium	撕裂、DMA、泡孔壁、壓縮永久變形 Tear strength, DMA, cell walls, and compression set
相容劑 Compatibilizer	0／低／中 0/Low/Medium	相尺寸、界面破壞、黏著 Domain size, interfacial failure, and adhesion
雙螺桿SME Twin-Screw SME	低／中／高 Low/Medium/High	團聚數、熔體溫度、MFR變化 Agglomerate count, melt temperature, and MFR change
DCP有效量 Effective DCP Dosage	低／中／高 Low/Medium/High	t10、t90、凝膠率、倍率 t10, t90, gel content, and expansion ratio
冷卻與後熟化 Cooling and Post-Conditioning	標準／加強 Standard/Enhanced	24／72 h尺寸與二次熱收縮 Dimensions at 24/72 h and secondary thermal shrinkage

比較時必須固定的條件

Conditions That Must Be Held Constant During Comparison

1. 成品密度與測試方向；否則硬度、回彈與撕裂不能公平比較。

Finished-product density and test direction; otherwise, hardness, resilience, and tear strength cannot be compared fairly.

2. EVA／POE／SEBS總聚合物基準與油品總量。

The total-polymer basis for EVA/POE/SEBS and the total amount of oil.

3. DCP的有效純度，而不是只比較商品添加重量。

The effective purity of DCP, rather than only the commercial-product addition weight.

4. 混煉機實際排膠溫度、母粒含水與停放時間。

The mixer's actual dump temperature, masterbatch moisture, and aging time.

5. 發泡模具、中心溫度、開模時間與冷卻方式。

Foaming mold, core temperature, demolding time, and cooling method.

建議的成功判定

Recommended Success Criteria

三層驗證｜第一層看母粒：沒有未熔粒、相尺寸穩定、MFR漂移可控；第二層看發泡：密度、泡孔與尺寸一致；第三層看使用：撕裂、壓縮永久變形、回彈及貼合後收縮優於原EVA／POE配方。 Three-level verification | Level 1, assess the masterbatch: no unmelted particles, stable domain size, and controlled MFR drift. Level 2, assess foaming: consistent density, cell structure, and dimensions. Level 3, assess use performance: tear strength, compression set, resilience, and post-lamination shrinkage are better than in the original EVA/POE formulation.

十、現場異常診斷表

X. On-Site Troubleshooting Table

異常 Symptom	可能原因 Possible Cause	優先改善 Priority Improvement
粒子有硬點 Hard Specks in Pellets	SEBS未塑化、喂料不穩、停留不足 Unplasticized SEBS, unstable feeding, or insufficient residence time	提高預熱／停留、調捏合區、改失重餵料 Increase preheating/residence time, adjust the kneading zone, and switch to loss-in-weight feeding.
MFR明顯上升 Marked Increase in MFR	剪切／熱氧降解 Shear/thermo-oxidative degradation	降低SME與熔體溫度、改善排氣與抗氧化 Reduce SME and melt temperature, and improve venting and antioxidant protection.
泡孔粗細差大 Large Variation in Cell Size	相尺寸不均、DCP／發泡劑分散不均 Nonuniform domain size or uneven dispersion of DCP/blowing agent	聚合物先預造粒；活性系統第二段加入 Pre-pelletize the polymers first; add the reactive system in the second stage.
撕裂反而下降 Tear Strength Decreases	SEBS團聚或弱界面 SEBS agglomeration or weak interfaces	檢查形態、黏度比與相容劑 Check morphology, viscosity ratio, and the compatibilizer.
貼合後收縮 Shrinkage After Lamination	POE低熔融支撐、交聯或冷卻不足 Insufficient low-temperature melt support from POE, crosslinking, or cooling	DSC＋MDR＋72 h尺寸；降低低熔點相比例 Use DSC, MDR, and 72 h dimensions; reduce the proportion of low-melting phases.
表面黏或滲油 Tacky Surface or Oil Bleed	SEBS充油過高或油相遷移 Excessive oil extension in SEBS or oil-phase migration	核對牌號含油量、總油量及吸油平衡 Verify the grade's oil content, total oil loading, and oil-absorption balance.

結論：SEBS的價值，不在「多一種料」，而在建立可控制的界面

Conclusion: The Value of SEBS Is Not Merely Adding Another Material, but Creating Controllable Interfaces

EVA加入POE，是發泡配方中有效的降硬與回彈策略，但當POE比例升高，結晶支撐、極性、交聯效率與尺寸穩定可能同時下降。SEBS可以利用PS硬微區與EB軟段，補強熔體彈性、撕裂與泡孔壁，並降低配方對單一低熔點POE的依賴。

Adding POE to EVA is an effective strategy for reducing hardness and improving resilience in foam formulations, but as the POE proportion rises, crystalline support, polarity, crosslinking efficiency, and dimensional stability may all decline. SEBS can use its hard PS microdomains and soft EB segments to reinforce melt elasticity, tear strength, and cell walls while reducing the formulation's dependence on a single low-melting POE.

然而，三元共混的成敗取決於相形態。SEBS如果沒有充分塑化與分散，只會變成凝膠粒、弱界面和發泡缺陷。雙螺桿預混煉的真正作用，是把相尺寸、界面更新、熱史與批次能量變成可量化的製程參數；再把DCP與發泡劑移到第二段低溫加入，才能同時兼顧安全、分散與交聯—產氣窗口。

The success of the ternary blend, however, depends on phase morphology. If SEBS is not fully plasticized and dispersed, it merely becomes gel particles, weak interfaces, and foaming defects. The true function of twin-screw pre-compounding is to turn domain size, interfacial renewal, thermal history, and batch energy into quantifiable process parameters. Moving DCP and the blowing agent to a second, low-temperature addition stage then makes it possible to balance safety, dispersion, and the crosslinking-gas-generation window.

研發決策一句話｜EVA／POE決定柔軟與回彈的底盤，SEBS負責補強界面與泡孔壁，雙螺桿則把材料潛力轉化為可重複的量產形態。 R&D decision in one sentence | EVA/POE establishes the foundation of softness and resilience, SEBS reinforces interfaces and cell walls, and the twin-screw process converts the material's potential into a reproducible morphology for mass production.